1 /*
2 * ng_base.c
3 */
4
5 /*-
6 * Copyright (c) 1996-1999 Whistle Communications, Inc.
7 * All rights reserved.
8 *
9 * Subject to the following obligations and disclaimer of warranty, use and
10 * redistribution of this software, in source or object code forms, with or
11 * without modifications are expressly permitted by Whistle Communications;
12 * provided, however, that:
13 * 1. Any and all reproductions of the source or object code must include the
14 * copyright notice above and the following disclaimer of warranties; and
15 * 2. No rights are granted, in any manner or form, to use Whistle
16 * Communications, Inc. trademarks, including the mark "WHISTLE
17 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as
18 * such appears in the above copyright notice or in the software.
19 *
20 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
21 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
22 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
23 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
24 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
25 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
26 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
27 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
28 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
29 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
30 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
31 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
32 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
36 * OF SUCH DAMAGE.
37 *
38 * Authors: Julian Elischer <julian@freebsd.org>
39 * Archie Cobbs <archie@freebsd.org>
40 *
41 * $FreeBSD$
42 * $Whistle: ng_base.c,v 1.39 1999/01/28 23:54:53 julian Exp $
43 */
44
45 /*
46 * This file implements the base netgraph code.
47 */
48
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/ctype.h>
52 #include <sys/errno.h>
53 #include <sys/kdb.h>
54 #include <sys/kernel.h>
55 #include <sys/ktr.h>
56 #include <sys/limits.h>
57 #include <sys/malloc.h>
58 #include <sys/mbuf.h>
59 #include <sys/queue.h>
60 #include <sys/sysctl.h>
61 #include <sys/syslog.h>
62 #include <sys/refcount.h>
63 #include <sys/proc.h>
64 #include <sys/unistd.h>
65 #include <sys/kthread.h>
66 #include <sys/smp.h>
67 #include <machine/cpu.h>
68
69 #include <netgraph/ng_message.h>
70 #include <netgraph/netgraph.h>
71 #include <netgraph/ng_parse.h>
72
73 MODULE_VERSION(netgraph, NG_ABI_VERSION);
74
75 /* Mutex to protect topology events. */
76 static struct mtx ng_topo_mtx;
77
78 #ifdef NETGRAPH_DEBUG
79 static struct mtx ng_nodelist_mtx; /* protects global node/hook lists */
80 static struct mtx ngq_mtx; /* protects the queue item list */
81
82 static SLIST_HEAD(, ng_node) ng_allnodes;
83 static LIST_HEAD(, ng_node) ng_freenodes; /* in debug, we never free() them */
84 static SLIST_HEAD(, ng_hook) ng_allhooks;
85 static LIST_HEAD(, ng_hook) ng_freehooks; /* in debug, we never free() them */
86
87 static void ng_dumpitems(void);
88 static void ng_dumpnodes(void);
89 static void ng_dumphooks(void);
90
91 #endif /* NETGRAPH_DEBUG */
92 /*
93 * DEAD versions of the structures.
94 * In order to avoid races, it is sometimes neccesary to point
95 * at SOMETHING even though theoretically, the current entity is
96 * INVALID. Use these to avoid these races.
97 */
98 struct ng_type ng_deadtype = {
99 NG_ABI_VERSION,
100 "dead",
101 NULL, /* modevent */
102 NULL, /* constructor */
103 NULL, /* rcvmsg */
104 NULL, /* shutdown */
105 NULL, /* newhook */
106 NULL, /* findhook */
107 NULL, /* connect */
108 NULL, /* rcvdata */
109 NULL, /* disconnect */
110 NULL, /* cmdlist */
111 };
112
113 struct ng_node ng_deadnode = {
114 "dead",
115 &ng_deadtype,
116 NGF_INVALID,
117 1, /* refs */
118 0, /* numhooks */
119 NULL, /* private */
120 0, /* ID */
121 LIST_HEAD_INITIALIZER(ng_deadnode.hooks),
122 {}, /* all_nodes list entry */
123 {}, /* id hashtable list entry */
124 {}, /* workqueue entry */
125 { 0,
126 {}, /* should never use! (should hang) */
127 NULL,
128 &ng_deadnode.nd_input_queue.queue,
129 &ng_deadnode
130 },
131 #ifdef NETGRAPH_DEBUG
132 ND_MAGIC,
133 __FILE__,
134 __LINE__,
135 {NULL}
136 #endif /* NETGRAPH_DEBUG */
137 };
138
139 struct ng_hook ng_deadhook = {
140 "dead",
141 NULL, /* private */
142 HK_INVALID | HK_DEAD,
143 1, /* refs always >= 1 */
144 0, /* undefined data link type */
145 &ng_deadhook, /* Peer is self */
146 &ng_deadnode, /* attached to deadnode */
147 {}, /* hooks list */
148 NULL, /* override rcvmsg() */
149 NULL, /* override rcvdata() */
150 #ifdef NETGRAPH_DEBUG
151 HK_MAGIC,
152 __FILE__,
153 __LINE__,
154 {NULL}
155 #endif /* NETGRAPH_DEBUG */
156 };
157
158 /*
159 * END DEAD STRUCTURES
160 */
161 /* List nodes with unallocated work */
162 static TAILQ_HEAD(, ng_node) ng_worklist = TAILQ_HEAD_INITIALIZER(ng_worklist);
163 static struct mtx ng_worklist_mtx; /* MUST LOCK NODE FIRST */
164
165 /* List of installed types */
166 static LIST_HEAD(, ng_type) ng_typelist;
167 static struct mtx ng_typelist_mtx;
168
169 /* Hash related definitions */
170 /* XXX Don't need to initialise them because it's a LIST */
171 #define NG_ID_HASH_SIZE 128 /* most systems wont need even this many */
172 static LIST_HEAD(, ng_node) ng_ID_hash[NG_ID_HASH_SIZE];
173 static struct mtx ng_idhash_mtx;
174 /* Method to find a node.. used twice so do it here */
175 #define NG_IDHASH_FN(ID) ((ID) % (NG_ID_HASH_SIZE))
176 #define NG_IDHASH_FIND(ID, node) \
177 do { \
178 mtx_assert(&ng_idhash_mtx, MA_OWNED); \
179 LIST_FOREACH(node, &ng_ID_hash[NG_IDHASH_FN(ID)], \
180 nd_idnodes) { \
181 if (NG_NODE_IS_VALID(node) \
182 && (NG_NODE_ID(node) == ID)) { \
183 break; \
184 } \
185 } \
186 } while (0)
187
188 #define NG_NAME_HASH_SIZE 128 /* most systems wont need even this many */
189 static LIST_HEAD(, ng_node) ng_name_hash[NG_NAME_HASH_SIZE];
190 static struct mtx ng_namehash_mtx;
191 #define NG_NAMEHASH(NAME, HASH) \
192 do { \
193 u_char h = 0; \
194 const u_char *c; \
195 for (c = (const u_char*)(NAME); *c; c++)\
196 h += *c; \
197 (HASH) = h % (NG_NAME_HASH_SIZE); \
198 } while (0)
199
200
201 /* Internal functions */
202 static int ng_add_hook(node_p node, const char *name, hook_p * hookp);
203 static int ng_generic_msg(node_p here, item_p item, hook_p lasthook);
204 static ng_ID_t ng_decodeidname(const char *name);
205 static int ngb_mod_event(module_t mod, int event, void *data);
206 static void ng_worklist_add(node_p node);
207 static void ngthread(void *);
208 static int ng_apply_item(node_p node, item_p item, int rw);
209 static void ng_flush_input_queue(struct ng_queue * ngq);
210 static node_p ng_ID2noderef(ng_ID_t ID);
211 static int ng_con_nodes(item_p item, node_p node, const char *name,
212 node_p node2, const char *name2);
213 static int ng_con_part2(node_p node, item_p item, hook_p hook);
214 static int ng_con_part3(node_p node, item_p item, hook_p hook);
215 static int ng_mkpeer(node_p node, const char *name,
216 const char *name2, char *type);
217
218 /* Imported, these used to be externally visible, some may go back. */
219 void ng_destroy_hook(hook_p hook);
220 node_p ng_name2noderef(node_p node, const char *name);
221 int ng_path2noderef(node_p here, const char *path,
222 node_p *dest, hook_p *lasthook);
223 int ng_make_node(const char *type, node_p *nodepp);
224 int ng_path_parse(char *addr, char **node, char **path, char **hook);
225 void ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3);
226 void ng_unname(node_p node);
227
228
229 /* Our own netgraph malloc type */
230 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages");
231 MALLOC_DEFINE(M_NETGRAPH_HOOK, "netgraph_hook", "netgraph hook structures");
232 MALLOC_DEFINE(M_NETGRAPH_NODE, "netgraph_node", "netgraph node structures");
233 MALLOC_DEFINE(M_NETGRAPH_ITEM, "netgraph_item", "netgraph item structures");
234 MALLOC_DEFINE(M_NETGRAPH_MSG, "netgraph_msg", "netgraph name storage");
235
236 /* Should not be visible outside this file */
237
238 #define _NG_ALLOC_HOOK(hook) \
239 MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH_HOOK, M_NOWAIT | M_ZERO)
240 #define _NG_ALLOC_NODE(node) \
241 MALLOC(node, node_p, sizeof(*node), M_NETGRAPH_NODE, M_NOWAIT | M_ZERO)
242
243 #define NG_QUEUE_LOCK_INIT(n) \
244 mtx_init(&(n)->q_mtx, "ng_node", NULL, MTX_DEF)
245 #define NG_QUEUE_LOCK(n) \
246 mtx_lock(&(n)->q_mtx)
247 #define NG_QUEUE_UNLOCK(n) \
248 mtx_unlock(&(n)->q_mtx)
249 #define NG_WORKLIST_LOCK_INIT() \
250 mtx_init(&ng_worklist_mtx, "ng_worklist", NULL, MTX_DEF)
251 #define NG_WORKLIST_LOCK() \
252 mtx_lock(&ng_worklist_mtx)
253 #define NG_WORKLIST_UNLOCK() \
254 mtx_unlock(&ng_worklist_mtx)
255 #define NG_WORKLIST_SLEEP() \
256 mtx_sleep(&ng_worklist, &ng_worklist_mtx, PI_NET, "sleep", 0)
257 #define NG_WORKLIST_WAKEUP() \
258 wakeup_one(&ng_worklist)
259
260 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/
261 /*
262 * In debug mode:
263 * In an attempt to help track reference count screwups
264 * we do not free objects back to the malloc system, but keep them
265 * in a local cache where we can examine them and keep information safely
266 * after they have been freed.
267 * We use this scheme for nodes and hooks, and to some extent for items.
268 */
269 static __inline hook_p
270 ng_alloc_hook(void)
271 {
272 hook_p hook;
273 SLIST_ENTRY(ng_hook) temp;
274 mtx_lock(&ng_nodelist_mtx);
275 hook = LIST_FIRST(&ng_freehooks);
276 if (hook) {
277 LIST_REMOVE(hook, hk_hooks);
278 bcopy(&hook->hk_all, &temp, sizeof(temp));
279 bzero(hook, sizeof(struct ng_hook));
280 bcopy(&temp, &hook->hk_all, sizeof(temp));
281 mtx_unlock(&ng_nodelist_mtx);
282 hook->hk_magic = HK_MAGIC;
283 } else {
284 mtx_unlock(&ng_nodelist_mtx);
285 _NG_ALLOC_HOOK(hook);
286 if (hook) {
287 hook->hk_magic = HK_MAGIC;
288 mtx_lock(&ng_nodelist_mtx);
289 SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all);
290 mtx_unlock(&ng_nodelist_mtx);
291 }
292 }
293 return (hook);
294 }
295
296 static __inline node_p
297 ng_alloc_node(void)
298 {
299 node_p node;
300 SLIST_ENTRY(ng_node) temp;
301 mtx_lock(&ng_nodelist_mtx);
302 node = LIST_FIRST(&ng_freenodes);
303 if (node) {
304 LIST_REMOVE(node, nd_nodes);
305 bcopy(&node->nd_all, &temp, sizeof(temp));
306 bzero(node, sizeof(struct ng_node));
307 bcopy(&temp, &node->nd_all, sizeof(temp));
308 mtx_unlock(&ng_nodelist_mtx);
309 node->nd_magic = ND_MAGIC;
310 } else {
311 mtx_unlock(&ng_nodelist_mtx);
312 _NG_ALLOC_NODE(node);
313 if (node) {
314 node->nd_magic = ND_MAGIC;
315 mtx_lock(&ng_nodelist_mtx);
316 SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all);
317 mtx_unlock(&ng_nodelist_mtx);
318 }
319 }
320 return (node);
321 }
322
323 #define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0)
324 #define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0)
325
326
327 #define NG_FREE_HOOK(hook) \
328 do { \
329 mtx_lock(&ng_nodelist_mtx); \
330 LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks); \
331 hook->hk_magic = 0; \
332 mtx_unlock(&ng_nodelist_mtx); \
333 } while (0)
334
335 #define NG_FREE_NODE(node) \
336 do { \
337 mtx_lock(&ng_nodelist_mtx); \
338 LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes); \
339 node->nd_magic = 0; \
340 mtx_unlock(&ng_nodelist_mtx); \
341 } while (0)
342
343 #else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
344
345 #define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook)
346 #define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node)
347
348 #define NG_FREE_HOOK(hook) do { FREE((hook), M_NETGRAPH_HOOK); } while (0)
349 #define NG_FREE_NODE(node) do { FREE((node), M_NETGRAPH_NODE); } while (0)
350
351 #endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
352
353 /* Set this to kdb_enter("X") to catch all errors as they occur */
354 #ifndef TRAP_ERROR
355 #define TRAP_ERROR()
356 #endif
357
358 static ng_ID_t nextID = 1;
359
360 #ifdef INVARIANTS
361 #define CHECK_DATA_MBUF(m) do { \
362 struct mbuf *n; \
363 int total; \
364 \
365 M_ASSERTPKTHDR(m); \
366 for (total = 0, n = (m); n != NULL; n = n->m_next) { \
367 total += n->m_len; \
368 if (n->m_nextpkt != NULL) \
369 panic("%s: m_nextpkt", __func__); \
370 } \
371 \
372 if ((m)->m_pkthdr.len != total) { \
373 panic("%s: %d != %d", \
374 __func__, (m)->m_pkthdr.len, total); \
375 } \
376 } while (0)
377 #else
378 #define CHECK_DATA_MBUF(m)
379 #endif
380
381 #define ERROUT(x) do { error = (x); goto done; } while (0)
382
383 /************************************************************************
384 Parse type definitions for generic messages
385 ************************************************************************/
386
387 /* Handy structure parse type defining macro */
388 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \
389 static const struct ng_parse_struct_field \
390 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \
391 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \
392 &ng_parse_struct_type, \
393 &ng_ ## lo ## _type_fields \
394 }
395
396 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ());
397 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ());
398 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ());
399 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ());
400 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ());
401 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ());
402 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type));
403
404 /* Get length of an array when the length is stored as a 32 bit
405 value immediately preceding the array -- as with struct namelist
406 and struct typelist. */
407 static int
408 ng_generic_list_getLength(const struct ng_parse_type *type,
409 const u_char *start, const u_char *buf)
410 {
411 return *((const u_int32_t *)(buf - 4));
412 }
413
414 /* Get length of the array of struct linkinfo inside a struct hooklist */
415 static int
416 ng_generic_linkinfo_getLength(const struct ng_parse_type *type,
417 const u_char *start, const u_char *buf)
418 {
419 const struct hooklist *hl = (const struct hooklist *)start;
420
421 return hl->nodeinfo.hooks;
422 }
423
424 /* Array type for a variable length array of struct namelist */
425 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = {
426 &ng_generic_nodeinfo_type,
427 &ng_generic_list_getLength
428 };
429 static const struct ng_parse_type ng_generic_nodeinfoarray_type = {
430 &ng_parse_array_type,
431 &ng_nodeinfoarray_type_info
432 };
433
434 /* Array type for a variable length array of struct typelist */
435 static const struct ng_parse_array_info ng_typeinfoarray_type_info = {
436 &ng_generic_typeinfo_type,
437 &ng_generic_list_getLength
438 };
439 static const struct ng_parse_type ng_generic_typeinfoarray_type = {
440 &ng_parse_array_type,
441 &ng_typeinfoarray_type_info
442 };
443
444 /* Array type for array of struct linkinfo in struct hooklist */
445 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = {
446 &ng_generic_linkinfo_type,
447 &ng_generic_linkinfo_getLength
448 };
449 static const struct ng_parse_type ng_generic_linkinfo_array_type = {
450 &ng_parse_array_type,
451 &ng_generic_linkinfo_array_type_info
452 };
453
454 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type));
455 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST,
456 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type));
457 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES,
458 (&ng_generic_nodeinfoarray_type));
459
460 /* List of commands and how to convert arguments to/from ASCII */
461 static const struct ng_cmdlist ng_generic_cmds[] = {
462 {
463 NGM_GENERIC_COOKIE,
464 NGM_SHUTDOWN,
465 "shutdown",
466 NULL,
467 NULL
468 },
469 {
470 NGM_GENERIC_COOKIE,
471 NGM_MKPEER,
472 "mkpeer",
473 &ng_generic_mkpeer_type,
474 NULL
475 },
476 {
477 NGM_GENERIC_COOKIE,
478 NGM_CONNECT,
479 "connect",
480 &ng_generic_connect_type,
481 NULL
482 },
483 {
484 NGM_GENERIC_COOKIE,
485 NGM_NAME,
486 "name",
487 &ng_generic_name_type,
488 NULL
489 },
490 {
491 NGM_GENERIC_COOKIE,
492 NGM_RMHOOK,
493 "rmhook",
494 &ng_generic_rmhook_type,
495 NULL
496 },
497 {
498 NGM_GENERIC_COOKIE,
499 NGM_NODEINFO,
500 "nodeinfo",
501 NULL,
502 &ng_generic_nodeinfo_type
503 },
504 {
505 NGM_GENERIC_COOKIE,
506 NGM_LISTHOOKS,
507 "listhooks",
508 NULL,
509 &ng_generic_hooklist_type
510 },
511 {
512 NGM_GENERIC_COOKIE,
513 NGM_LISTNAMES,
514 "listnames",
515 NULL,
516 &ng_generic_listnodes_type /* same as NGM_LISTNODES */
517 },
518 {
519 NGM_GENERIC_COOKIE,
520 NGM_LISTNODES,
521 "listnodes",
522 NULL,
523 &ng_generic_listnodes_type
524 },
525 {
526 NGM_GENERIC_COOKIE,
527 NGM_LISTTYPES,
528 "listtypes",
529 NULL,
530 &ng_generic_typeinfo_type
531 },
532 {
533 NGM_GENERIC_COOKIE,
534 NGM_TEXT_CONFIG,
535 "textconfig",
536 NULL,
537 &ng_parse_string_type
538 },
539 {
540 NGM_GENERIC_COOKIE,
541 NGM_TEXT_STATUS,
542 "textstatus",
543 NULL,
544 &ng_parse_string_type
545 },
546 {
547 NGM_GENERIC_COOKIE,
548 NGM_ASCII2BINARY,
549 "ascii2binary",
550 &ng_parse_ng_mesg_type,
551 &ng_parse_ng_mesg_type
552 },
553 {
554 NGM_GENERIC_COOKIE,
555 NGM_BINARY2ASCII,
556 "binary2ascii",
557 &ng_parse_ng_mesg_type,
558 &ng_parse_ng_mesg_type
559 },
560 { 0 }
561 };
562
563 /************************************************************************
564 Node routines
565 ************************************************************************/
566
567 /*
568 * Instantiate a node of the requested type
569 */
570 int
571 ng_make_node(const char *typename, node_p *nodepp)
572 {
573 struct ng_type *type;
574 int error;
575
576 /* Check that the type makes sense */
577 if (typename == NULL) {
578 TRAP_ERROR();
579 return (EINVAL);
580 }
581
582 /* Locate the node type. If we fail we return. Do not try to load
583 * module.
584 */
585 if ((type = ng_findtype(typename)) == NULL)
586 return (ENXIO);
587
588 /*
589 * If we have a constructor, then make the node and
590 * call the constructor to do type specific initialisation.
591 */
592 if (type->constructor != NULL) {
593 if ((error = ng_make_node_common(type, nodepp)) == 0) {
594 if ((error = ((*type->constructor)(*nodepp)) != 0)) {
595 NG_NODE_UNREF(*nodepp);
596 }
597 }
598 } else {
599 /*
600 * Node has no constructor. We cannot ask for one
601 * to be made. It must be brought into existence by
602 * some external agency. The external agency should
603 * call ng_make_node_common() directly to get the
604 * netgraph part initialised.
605 */
606 TRAP_ERROR();
607 error = EINVAL;
608 }
609 return (error);
610 }
611
612 /*
613 * Generic node creation. Called by node initialisation for externally
614 * instantiated nodes (e.g. hardware, sockets, etc ).
615 * The returned node has a reference count of 1.
616 */
617 int
618 ng_make_node_common(struct ng_type *type, node_p *nodepp)
619 {
620 node_p node;
621
622 /* Require the node type to have been already installed */
623 if (ng_findtype(type->name) == NULL) {
624 TRAP_ERROR();
625 return (EINVAL);
626 }
627
628 /* Make a node and try attach it to the type */
629 NG_ALLOC_NODE(node);
630 if (node == NULL) {
631 TRAP_ERROR();
632 return (ENOMEM);
633 }
634 node->nd_type = type;
635 NG_NODE_REF(node); /* note reference */
636 type->refs++;
637
638 NG_QUEUE_LOCK_INIT(&node->nd_input_queue);
639 node->nd_input_queue.queue = NULL;
640 node->nd_input_queue.last = &node->nd_input_queue.queue;
641 node->nd_input_queue.q_flags = 0;
642 node->nd_input_queue.q_node = node;
643
644 /* Initialize hook list for new node */
645 LIST_INIT(&node->nd_hooks);
646
647 /* Link us into the name hash. */
648 mtx_lock(&ng_namehash_mtx);
649 LIST_INSERT_HEAD(&ng_name_hash[0], node, nd_nodes);
650 mtx_unlock(&ng_namehash_mtx);
651
652 /* get an ID and put us in the hash chain */
653 mtx_lock(&ng_idhash_mtx);
654 for (;;) { /* wrap protection, even if silly */
655 node_p node2 = NULL;
656 node->nd_ID = nextID++; /* 137/second for 1 year before wrap */
657
658 /* Is there a problem with the new number? */
659 NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */
660 if ((node->nd_ID != 0) && (node2 == NULL)) {
661 break;
662 }
663 }
664 LIST_INSERT_HEAD(&ng_ID_hash[NG_IDHASH_FN(node->nd_ID)],
665 node, nd_idnodes);
666 mtx_unlock(&ng_idhash_mtx);
667
668 /* Done */
669 *nodepp = node;
670 return (0);
671 }
672
673 /*
674 * Forceably start the shutdown process on a node. Either call
675 * its shutdown method, or do the default shutdown if there is
676 * no type-specific method.
677 *
678 * We can only be called from a shutdown message, so we know we have
679 * a writer lock, and therefore exclusive access. It also means
680 * that we should not be on the work queue, but we check anyhow.
681 *
682 * Persistent node types must have a type-specific method which
683 * allocates a new node in which case, this one is irretrievably going away,
684 * or cleans up anything it needs, and just makes the node valid again,
685 * in which case we allow the node to survive.
686 *
687 * XXX We need to think of how to tell a persistent node that we
688 * REALLY need to go away because the hardware has gone or we
689 * are rebooting.... etc.
690 */
691 void
692 ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3)
693 {
694 hook_p hook;
695
696 /* Check if it's already shutting down */
697 if ((node->nd_flags & NGF_CLOSING) != 0)
698 return;
699
700 if (node == &ng_deadnode) {
701 printf ("shutdown called on deadnode\n");
702 return;
703 }
704
705 /* Add an extra reference so it doesn't go away during this */
706 NG_NODE_REF(node);
707
708 /*
709 * Mark it invalid so any newcomers know not to try use it
710 * Also add our own mark so we can't recurse
711 * note that NGF_INVALID does not do this as it's also set during
712 * creation
713 */
714 node->nd_flags |= NGF_INVALID|NGF_CLOSING;
715
716 /* If node has its pre-shutdown method, then call it first*/
717 if (node->nd_type && node->nd_type->close)
718 (*node->nd_type->close)(node);
719
720 /* Notify all remaining connected nodes to disconnect */
721 while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL)
722 ng_destroy_hook(hook);
723
724 /*
725 * Drain the input queue forceably.
726 * it has no hooks so what's it going to do, bleed on someone?
727 * Theoretically we came here from a queue entry that was added
728 * Just before the queue was closed, so it should be empty anyway.
729 * Also removes us from worklist if needed.
730 */
731 ng_flush_input_queue(&node->nd_input_queue);
732
733 /* Ask the type if it has anything to do in this case */
734 if (node->nd_type && node->nd_type->shutdown) {
735 (*node->nd_type->shutdown)(node);
736 if (NG_NODE_IS_VALID(node)) {
737 /*
738 * Well, blow me down if the node code hasn't declared
739 * that it doesn't want to die.
740 * Presumably it is a persistant node.
741 * If we REALLY want it to go away,
742 * e.g. hardware going away,
743 * Our caller should set NGF_REALLY_DIE in nd_flags.
744 */
745 node->nd_flags &= ~(NGF_INVALID|NGF_CLOSING);
746 NG_NODE_UNREF(node); /* Assume they still have theirs */
747 return;
748 }
749 } else { /* do the default thing */
750 NG_NODE_UNREF(node);
751 }
752
753 ng_unname(node); /* basically a NOP these days */
754
755 /*
756 * Remove extra reference, possibly the last
757 * Possible other holders of references may include
758 * timeout callouts, but theoretically the node's supposed to
759 * have cancelled them. Possibly hardware dependencies may
760 * force a driver to 'linger' with a reference.
761 */
762 NG_NODE_UNREF(node);
763 }
764
765 /*
766 * Remove a reference to the node, possibly the last.
767 * deadnode always acts as it it were the last.
768 */
769 int
770 ng_unref_node(node_p node)
771 {
772 int v;
773
774 if (node == &ng_deadnode) {
775 return (0);
776 }
777
778 v = atomic_fetchadd_int(&node->nd_refs, -1);
779
780 if (v == 1) { /* we were the last */
781
782 mtx_lock(&ng_namehash_mtx);
783 node->nd_type->refs--; /* XXX maybe should get types lock? */
784 LIST_REMOVE(node, nd_nodes);
785 mtx_unlock(&ng_namehash_mtx);
786
787 mtx_lock(&ng_idhash_mtx);
788 LIST_REMOVE(node, nd_idnodes);
789 mtx_unlock(&ng_idhash_mtx);
790
791 mtx_destroy(&node->nd_input_queue.q_mtx);
792 NG_FREE_NODE(node);
793 }
794 return (v - 1);
795 }
796
797 /************************************************************************
798 Node ID handling
799 ************************************************************************/
800 static node_p
801 ng_ID2noderef(ng_ID_t ID)
802 {
803 node_p node;
804 mtx_lock(&ng_idhash_mtx);
805 NG_IDHASH_FIND(ID, node);
806 if(node)
807 NG_NODE_REF(node);
808 mtx_unlock(&ng_idhash_mtx);
809 return(node);
810 }
811
812 ng_ID_t
813 ng_node2ID(node_p node)
814 {
815 return (node ? NG_NODE_ID(node) : 0);
816 }
817
818 /************************************************************************
819 Node name handling
820 ************************************************************************/
821
822 /*
823 * Assign a node a name. Once assigned, the name cannot be changed.
824 */
825 int
826 ng_name_node(node_p node, const char *name)
827 {
828 int i, hash;
829 node_p node2;
830
831 /* Check the name is valid */
832 for (i = 0; i < NG_NODESIZ; i++) {
833 if (name[i] == '\0' || name[i] == '.' || name[i] == ':')
834 break;
835 }
836 if (i == 0 || name[i] != '\0') {
837 TRAP_ERROR();
838 return (EINVAL);
839 }
840 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */
841 TRAP_ERROR();
842 return (EINVAL);
843 }
844
845 /* Check the name isn't already being used */
846 if ((node2 = ng_name2noderef(node, name)) != NULL) {
847 NG_NODE_UNREF(node2);
848 TRAP_ERROR();
849 return (EADDRINUSE);
850 }
851
852 /* copy it */
853 strlcpy(NG_NODE_NAME(node), name, NG_NODESIZ);
854
855 /* Update name hash. */
856 NG_NAMEHASH(name, hash);
857 mtx_lock(&ng_namehash_mtx);
858 LIST_REMOVE(node, nd_nodes);
859 LIST_INSERT_HEAD(&ng_name_hash[hash], node, nd_nodes);
860 mtx_unlock(&ng_namehash_mtx);
861
862 return (0);
863 }
864
865 /*
866 * Find a node by absolute name. The name should NOT end with ':'
867 * The name "." means "this node" and "[xxx]" means "the node
868 * with ID (ie, at address) xxx".
869 *
870 * Returns the node if found, else NULL.
871 * Eventually should add something faster than a sequential search.
872 * Note it acquires a reference on the node so you can be sure it's still
873 * there.
874 */
875 node_p
876 ng_name2noderef(node_p here, const char *name)
877 {
878 node_p node;
879 ng_ID_t temp;
880 int hash;
881
882 /* "." means "this node" */
883 if (strcmp(name, ".") == 0) {
884 NG_NODE_REF(here);
885 return(here);
886 }
887
888 /* Check for name-by-ID */
889 if ((temp = ng_decodeidname(name)) != 0) {
890 return (ng_ID2noderef(temp));
891 }
892
893 /* Find node by name */
894 NG_NAMEHASH(name, hash);
895 mtx_lock(&ng_namehash_mtx);
896 LIST_FOREACH(node, &ng_name_hash[hash], nd_nodes) {
897 if (NG_NODE_IS_VALID(node) &&
898 (strcmp(NG_NODE_NAME(node), name) == 0)) {
899 break;
900 }
901 }
902 if (node)
903 NG_NODE_REF(node);
904 mtx_unlock(&ng_namehash_mtx);
905 return (node);
906 }
907
908 /*
909 * Decode an ID name, eg. "[f03034de]". Returns 0 if the
910 * string is not valid, otherwise returns the value.
911 */
912 static ng_ID_t
913 ng_decodeidname(const char *name)
914 {
915 const int len = strlen(name);
916 char *eptr;
917 u_long val;
918
919 /* Check for proper length, brackets, no leading junk */
920 if ((len < 3)
921 || (name[0] != '[')
922 || (name[len - 1] != ']')
923 || (!isxdigit(name[1]))) {
924 return ((ng_ID_t)0);
925 }
926
927 /* Decode number */
928 val = strtoul(name + 1, &eptr, 16);
929 if ((eptr - name != len - 1)
930 || (val == ULONG_MAX)
931 || (val == 0)) {
932 return ((ng_ID_t)0);
933 }
934 return (ng_ID_t)val;
935 }
936
937 /*
938 * Remove a name from a node. This should only be called
939 * when shutting down and removing the node.
940 * IF we allow name changing this may be more resurrected.
941 */
942 void
943 ng_unname(node_p node)
944 {
945 }
946
947 /************************************************************************
948 Hook routines
949 Names are not optional. Hooks are always connected, except for a
950 brief moment within these routines. On invalidation or during creation
951 they are connected to the 'dead' hook.
952 ************************************************************************/
953
954 /*
955 * Remove a hook reference
956 */
957 void
958 ng_unref_hook(hook_p hook)
959 {
960 int v;
961
962 if (hook == &ng_deadhook) {
963 return;
964 }
965
966 v = atomic_fetchadd_int(&hook->hk_refs, -1);
967
968 if (v == 1) { /* we were the last */
969 if (_NG_HOOK_NODE(hook)) /* it'll probably be ng_deadnode */
970 _NG_NODE_UNREF((_NG_HOOK_NODE(hook)));
971 NG_FREE_HOOK(hook);
972 }
973 }
974
975 /*
976 * Add an unconnected hook to a node. Only used internally.
977 * Assumes node is locked. (XXX not yet true )
978 */
979 static int
980 ng_add_hook(node_p node, const char *name, hook_p *hookp)
981 {
982 hook_p hook;
983 int error = 0;
984
985 /* Check that the given name is good */
986 if (name == NULL) {
987 TRAP_ERROR();
988 return (EINVAL);
989 }
990 if (ng_findhook(node, name) != NULL) {
991 TRAP_ERROR();
992 return (EEXIST);
993 }
994
995 /* Allocate the hook and link it up */
996 NG_ALLOC_HOOK(hook);
997 if (hook == NULL) {
998 TRAP_ERROR();
999 return (ENOMEM);
1000 }
1001 hook->hk_refs = 1; /* add a reference for us to return */
1002 hook->hk_flags = HK_INVALID;
1003 hook->hk_peer = &ng_deadhook; /* start off this way */
1004 hook->hk_node = node;
1005 NG_NODE_REF(node); /* each hook counts as a reference */
1006
1007 /* Set hook name */
1008 strlcpy(NG_HOOK_NAME(hook), name, NG_HOOKSIZ);
1009
1010 /*
1011 * Check if the node type code has something to say about it
1012 * If it fails, the unref of the hook will also unref the node.
1013 */
1014 if (node->nd_type->newhook != NULL) {
1015 if ((error = (*node->nd_type->newhook)(node, hook, name))) {
1016 NG_HOOK_UNREF(hook); /* this frees the hook */
1017 return (error);
1018 }
1019 }
1020 /*
1021 * The 'type' agrees so far, so go ahead and link it in.
1022 * We'll ask again later when we actually connect the hooks.
1023 */
1024 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks);
1025 node->nd_numhooks++;
1026 NG_HOOK_REF(hook); /* one for the node */
1027
1028 if (hookp)
1029 *hookp = hook;
1030 return (0);
1031 }
1032
1033 /*
1034 * Find a hook
1035 *
1036 * Node types may supply their own optimized routines for finding
1037 * hooks. If none is supplied, we just do a linear search.
1038 * XXX Possibly we should add a reference to the hook?
1039 */
1040 hook_p
1041 ng_findhook(node_p node, const char *name)
1042 {
1043 hook_p hook;
1044
1045 if (node->nd_type->findhook != NULL)
1046 return (*node->nd_type->findhook)(node, name);
1047 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
1048 if (NG_HOOK_IS_VALID(hook)
1049 && (strcmp(NG_HOOK_NAME(hook), name) == 0))
1050 return (hook);
1051 }
1052 return (NULL);
1053 }
1054
1055 /*
1056 * Destroy a hook
1057 *
1058 * As hooks are always attached, this really destroys two hooks.
1059 * The one given, and the one attached to it. Disconnect the hooks
1060 * from each other first. We reconnect the peer hook to the 'dead'
1061 * hook so that it can still exist after we depart. We then
1062 * send the peer its own destroy message. This ensures that we only
1063 * interact with the peer's structures when it is locked processing that
1064 * message. We hold a reference to the peer hook so we are guaranteed that
1065 * the peer hook and node are still going to exist until
1066 * we are finished there as the hook holds a ref on the node.
1067 * We run this same code again on the peer hook, but that time it is already
1068 * attached to the 'dead' hook.
1069 *
1070 * This routine is called at all stages of hook creation
1071 * on error detection and must be able to handle any such stage.
1072 */
1073 void
1074 ng_destroy_hook(hook_p hook)
1075 {
1076 hook_p peer;
1077 node_p node;
1078
1079 if (hook == &ng_deadhook) { /* better safe than sorry */
1080 printf("ng_destroy_hook called on deadhook\n");
1081 return;
1082 }
1083
1084 /*
1085 * Protect divorce process with mutex, to avoid races on
1086 * simultaneous disconnect.
1087 */
1088 mtx_lock(&ng_topo_mtx);
1089
1090 hook->hk_flags |= HK_INVALID;
1091
1092 peer = NG_HOOK_PEER(hook);
1093 node = NG_HOOK_NODE(hook);
1094
1095 if (peer && (peer != &ng_deadhook)) {
1096 /*
1097 * Set the peer to point to ng_deadhook
1098 * from this moment on we are effectively independent it.
1099 * send it an rmhook message of it's own.
1100 */
1101 peer->hk_peer = &ng_deadhook; /* They no longer know us */
1102 hook->hk_peer = &ng_deadhook; /* Nor us, them */
1103 if (NG_HOOK_NODE(peer) == &ng_deadnode) {
1104 /*
1105 * If it's already divorced from a node,
1106 * just free it.
1107 */
1108 mtx_unlock(&ng_topo_mtx);
1109 } else {
1110 mtx_unlock(&ng_topo_mtx);
1111 ng_rmhook_self(peer); /* Send it a surprise */
1112 }
1113 NG_HOOK_UNREF(peer); /* account for peer link */
1114 NG_HOOK_UNREF(hook); /* account for peer link */
1115 } else
1116 mtx_unlock(&ng_topo_mtx);
1117
1118 mtx_assert(&ng_topo_mtx, MA_NOTOWNED);
1119
1120 /*
1121 * Remove the hook from the node's list to avoid possible recursion
1122 * in case the disconnection results in node shutdown.
1123 */
1124 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */
1125 return;
1126 }
1127 LIST_REMOVE(hook, hk_hooks);
1128 node->nd_numhooks--;
1129 if (node->nd_type->disconnect) {
1130 /*
1131 * The type handler may elect to destroy the node so don't
1132 * trust its existence after this point. (except
1133 * that we still hold a reference on it. (which we
1134 * inherrited from the hook we are destroying)
1135 */
1136 (*node->nd_type->disconnect) (hook);
1137 }
1138
1139 /*
1140 * Note that because we will point to ng_deadnode, the original node
1141 * is not decremented automatically so we do that manually.
1142 */
1143 _NG_HOOK_NODE(hook) = &ng_deadnode;
1144 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */
1145 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */
1146 }
1147
1148 /*
1149 * Take two hooks on a node and merge the connection so that the given node
1150 * is effectively bypassed.
1151 */
1152 int
1153 ng_bypass(hook_p hook1, hook_p hook2)
1154 {
1155 if (hook1->hk_node != hook2->hk_node) {
1156 TRAP_ERROR();
1157 return (EINVAL);
1158 }
1159 hook1->hk_peer->hk_peer = hook2->hk_peer;
1160 hook2->hk_peer->hk_peer = hook1->hk_peer;
1161
1162 hook1->hk_peer = &ng_deadhook;
1163 hook2->hk_peer = &ng_deadhook;
1164
1165 NG_HOOK_UNREF(hook1);
1166 NG_HOOK_UNREF(hook2);
1167
1168 /* XXX If we ever cache methods on hooks update them as well */
1169 ng_destroy_hook(hook1);
1170 ng_destroy_hook(hook2);
1171 return (0);
1172 }
1173
1174 /*
1175 * Install a new netgraph type
1176 */
1177 int
1178 ng_newtype(struct ng_type *tp)
1179 {
1180 const size_t namelen = strlen(tp->name);
1181
1182 /* Check version and type name fields */
1183 if ((tp->version != NG_ABI_VERSION)
1184 || (namelen == 0)
1185 || (namelen >= NG_TYPESIZ)) {
1186 TRAP_ERROR();
1187 if (tp->version != NG_ABI_VERSION) {
1188 printf("Netgraph: Node type rejected. ABI mismatch. Suggest recompile\n");
1189 }
1190 return (EINVAL);
1191 }
1192
1193 /* Check for name collision */
1194 if (ng_findtype(tp->name) != NULL) {
1195 TRAP_ERROR();
1196 return (EEXIST);
1197 }
1198
1199
1200 /* Link in new type */
1201 mtx_lock(&ng_typelist_mtx);
1202 LIST_INSERT_HEAD(&ng_typelist, tp, types);
1203 tp->refs = 1; /* first ref is linked list */
1204 mtx_unlock(&ng_typelist_mtx);
1205 return (0);
1206 }
1207
1208 /*
1209 * unlink a netgraph type
1210 * If no examples exist
1211 */
1212 int
1213 ng_rmtype(struct ng_type *tp)
1214 {
1215 /* Check for name collision */
1216 if (tp->refs != 1) {
1217 TRAP_ERROR();
1218 return (EBUSY);
1219 }
1220
1221 /* Unlink type */
1222 mtx_lock(&ng_typelist_mtx);
1223 LIST_REMOVE(tp, types);
1224 mtx_unlock(&ng_typelist_mtx);
1225 return (0);
1226 }
1227
1228 /*
1229 * Look for a type of the name given
1230 */
1231 struct ng_type *
1232 ng_findtype(const char *typename)
1233 {
1234 struct ng_type *type;
1235
1236 mtx_lock(&ng_typelist_mtx);
1237 LIST_FOREACH(type, &ng_typelist, types) {
1238 if (strcmp(type->name, typename) == 0)
1239 break;
1240 }
1241 mtx_unlock(&ng_typelist_mtx);
1242 return (type);
1243 }
1244
1245 /************************************************************************
1246 Composite routines
1247 ************************************************************************/
1248 /*
1249 * Connect two nodes using the specified hooks, using queued functions.
1250 */
1251 static int
1252 ng_con_part3(node_p node, item_p item, hook_p hook)
1253 {
1254 int error = 0;
1255
1256 /*
1257 * When we run, we know that the node 'node' is locked for us.
1258 * Our caller has a reference on the hook.
1259 * Our caller has a reference on the node.
1260 * (In this case our caller is ng_apply_item() ).
1261 * The peer hook has a reference on the hook.
1262 * We are all set up except for the final call to the node, and
1263 * the clearing of the INVALID flag.
1264 */
1265 if (NG_HOOK_NODE(hook) == &ng_deadnode) {
1266 /*
1267 * The node must have been freed again since we last visited
1268 * here. ng_destry_hook() has this effect but nothing else does.
1269 * We should just release our references and
1270 * free anything we can think of.
1271 * Since we know it's been destroyed, and it's our caller
1272 * that holds the references, just return.
1273 */
1274 ERROUT(ENOENT);
1275 }
1276 if (hook->hk_node->nd_type->connect) {
1277 if ((error = (*hook->hk_node->nd_type->connect) (hook))) {
1278 ng_destroy_hook(hook); /* also zaps peer */
1279 printf("failed in ng_con_part3()\n");
1280 ERROUT(error);
1281 }
1282 }
1283 /*
1284 * XXX this is wrong for SMP. Possibly we need
1285 * to separate out 'create' and 'invalid' flags.
1286 * should only set flags on hooks we have locked under our node.
1287 */
1288 hook->hk_flags &= ~HK_INVALID;
1289 done:
1290 NG_FREE_ITEM(item);
1291 return (error);
1292 }
1293
1294 static int
1295 ng_con_part2(node_p node, item_p item, hook_p hook)
1296 {
1297 hook_p peer;
1298 int error = 0;
1299
1300 /*
1301 * When we run, we know that the node 'node' is locked for us.
1302 * Our caller has a reference on the hook.
1303 * Our caller has a reference on the node.
1304 * (In this case our caller is ng_apply_item() ).
1305 * The peer hook has a reference on the hook.
1306 * our node pointer points to the 'dead' node.
1307 * First check the hook name is unique.
1308 * Should not happen because we checked before queueing this.
1309 */
1310 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) {
1311 TRAP_ERROR();
1312 ng_destroy_hook(hook); /* should destroy peer too */
1313 printf("failed in ng_con_part2()\n");
1314 ERROUT(EEXIST);
1315 }
1316 /*
1317 * Check if the node type code has something to say about it
1318 * If it fails, the unref of the hook will also unref the attached node,
1319 * however since that node is 'ng_deadnode' this will do nothing.
1320 * The peer hook will also be destroyed.
1321 */
1322 if (node->nd_type->newhook != NULL) {
1323 if ((error = (*node->nd_type->newhook)(node, hook,
1324 hook->hk_name))) {
1325 ng_destroy_hook(hook); /* should destroy peer too */
1326 printf("failed in ng_con_part2()\n");
1327 ERROUT(error);
1328 }
1329 }
1330
1331 /*
1332 * The 'type' agrees so far, so go ahead and link it in.
1333 * We'll ask again later when we actually connect the hooks.
1334 */
1335 hook->hk_node = node; /* just overwrite ng_deadnode */
1336 NG_NODE_REF(node); /* each hook counts as a reference */
1337 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks);
1338 node->nd_numhooks++;
1339 NG_HOOK_REF(hook); /* one for the node */
1340
1341 /*
1342 * We now have a symmetrical situation, where both hooks have been
1343 * linked to their nodes, the newhook methods have been called
1344 * And the references are all correct. The hooks are still marked
1345 * as invalid, as we have not called the 'connect' methods
1346 * yet.
1347 * We can call the local one immediately as we have the
1348 * node locked, but we need to queue the remote one.
1349 */
1350 if (hook->hk_node->nd_type->connect) {
1351 if ((error = (*hook->hk_node->nd_type->connect) (hook))) {
1352 ng_destroy_hook(hook); /* also zaps peer */
1353 printf("failed in ng_con_part2(A)\n");
1354 ERROUT(error);
1355 }
1356 }
1357
1358 /*
1359 * Acquire topo mutex to avoid race with ng_destroy_hook().
1360 */
1361 mtx_lock(&ng_topo_mtx);
1362 peer = hook->hk_peer;
1363 if (peer == &ng_deadhook) {
1364 mtx_unlock(&ng_topo_mtx);
1365 printf("failed in ng_con_part2(B)\n");
1366 ng_destroy_hook(hook);
1367 ERROUT(ENOENT);
1368 }
1369 mtx_unlock(&ng_topo_mtx);
1370
1371 if ((error = ng_send_fn2(peer->hk_node, peer, item, &ng_con_part3,
1372 NULL, 0, NG_REUSE_ITEM))) {
1373 printf("failed in ng_con_part2(C)\n");
1374 ng_destroy_hook(hook); /* also zaps peer */
1375 return (error); /* item was consumed. */
1376 }
1377 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */
1378 return (0); /* item was consumed. */
1379 done:
1380 NG_FREE_ITEM(item);
1381 return (error);
1382 }
1383
1384 /*
1385 * Connect this node with another node. We assume that this node is
1386 * currently locked, as we are only called from an NGM_CONNECT message.
1387 */
1388 static int
1389 ng_con_nodes(item_p item, node_p node, const char *name,
1390 node_p node2, const char *name2)
1391 {
1392 int error;
1393 hook_p hook;
1394 hook_p hook2;
1395
1396 if (ng_findhook(node2, name2) != NULL) {
1397 return(EEXIST);
1398 }
1399 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */
1400 return (error);
1401 /* Allocate the other hook and link it up */
1402 NG_ALLOC_HOOK(hook2);
1403 if (hook2 == NULL) {
1404 TRAP_ERROR();
1405 ng_destroy_hook(hook); /* XXX check ref counts so far */
1406 NG_HOOK_UNREF(hook); /* including our ref */
1407 return (ENOMEM);
1408 }
1409 hook2->hk_refs = 1; /* start with a reference for us. */
1410 hook2->hk_flags = HK_INVALID;
1411 hook2->hk_peer = hook; /* Link the two together */
1412 hook->hk_peer = hook2;
1413 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/
1414 NG_HOOK_REF(hook2);
1415 hook2->hk_node = &ng_deadnode;
1416 strlcpy(NG_HOOK_NAME(hook2), name2, NG_HOOKSIZ);
1417
1418 /*
1419 * Queue the function above.
1420 * Procesing continues in that function in the lock context of
1421 * the other node.
1422 */
1423 if ((error = ng_send_fn2(node2, hook2, item, &ng_con_part2, NULL, 0,
1424 NG_NOFLAGS))) {
1425 printf("failed in ng_con_nodes(): %d\n", error);
1426 ng_destroy_hook(hook); /* also zaps peer */
1427 }
1428
1429 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */
1430 NG_HOOK_UNREF(hook2);
1431 return (error);
1432 }
1433
1434 /*
1435 * Make a peer and connect.
1436 * We assume that the local node is locked.
1437 * The new node probably doesn't need a lock until
1438 * it has a hook, because it cannot really have any work until then,
1439 * but we should think about it a bit more.
1440 *
1441 * The problem may come if the other node also fires up
1442 * some hardware or a timer or some other source of activation,
1443 * also it may already get a command msg via it's ID.
1444 *
1445 * We could use the same method as ng_con_nodes() but we'd have
1446 * to add ability to remove the node when failing. (Not hard, just
1447 * make arg1 point to the node to remove).
1448 * Unless of course we just ignore failure to connect and leave
1449 * an unconnected node?
1450 */
1451 static int
1452 ng_mkpeer(node_p node, const char *name, const char *name2, char *type)
1453 {
1454 node_p node2;
1455 hook_p hook1, hook2;
1456 int error;
1457
1458 if ((error = ng_make_node(type, &node2))) {
1459 return (error);
1460 }
1461
1462 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */
1463 ng_rmnode(node2, NULL, NULL, 0);
1464 return (error);
1465 }
1466
1467 if ((error = ng_add_hook(node2, name2, &hook2))) {
1468 ng_rmnode(node2, NULL, NULL, 0);
1469 ng_destroy_hook(hook1);
1470 NG_HOOK_UNREF(hook1);
1471 return (error);
1472 }
1473
1474 /*
1475 * Actually link the two hooks together.
1476 */
1477 hook1->hk_peer = hook2;
1478 hook2->hk_peer = hook1;
1479
1480 /* Each hook is referenced by the other */
1481 NG_HOOK_REF(hook1);
1482 NG_HOOK_REF(hook2);
1483
1484 /* Give each node the opportunity to veto the pending connection */
1485 if (hook1->hk_node->nd_type->connect) {
1486 error = (*hook1->hk_node->nd_type->connect) (hook1);
1487 }
1488
1489 if ((error == 0) && hook2->hk_node->nd_type->connect) {
1490 error = (*hook2->hk_node->nd_type->connect) (hook2);
1491
1492 }
1493
1494 /*
1495 * drop the references we were holding on the two hooks.
1496 */
1497 if (error) {
1498 ng_destroy_hook(hook2); /* also zaps hook1 */
1499 ng_rmnode(node2, NULL, NULL, 0);
1500 } else {
1501 /* As a last act, allow the hooks to be used */
1502 hook1->hk_flags &= ~HK_INVALID;
1503 hook2->hk_flags &= ~HK_INVALID;
1504 }
1505 NG_HOOK_UNREF(hook1);
1506 NG_HOOK_UNREF(hook2);
1507 return (error);
1508 }
1509
1510 /************************************************************************
1511 Utility routines to send self messages
1512 ************************************************************************/
1513
1514 /* Shut this node down as soon as everyone is clear of it */
1515 /* Should add arg "immediately" to jump the queue */
1516 int
1517 ng_rmnode_self(node_p node)
1518 {
1519 int error;
1520
1521 if (node == &ng_deadnode)
1522 return (0);
1523 node->nd_flags |= NGF_INVALID;
1524 if (node->nd_flags & NGF_CLOSING)
1525 return (0);
1526
1527 error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0);
1528 return (error);
1529 }
1530
1531 static void
1532 ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2)
1533 {
1534 ng_destroy_hook(hook);
1535 return ;
1536 }
1537
1538 int
1539 ng_rmhook_self(hook_p hook)
1540 {
1541 int error;
1542 node_p node = NG_HOOK_NODE(hook);
1543
1544 if (node == &ng_deadnode)
1545 return (0);
1546
1547 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0);
1548 return (error);
1549 }
1550
1551 /***********************************************************************
1552 * Parse and verify a string of the form: <NODE:><PATH>
1553 *
1554 * Such a string can refer to a specific node or a specific hook
1555 * on a specific node, depending on how you look at it. In the
1556 * latter case, the PATH component must not end in a dot.
1557 *
1558 * Both <NODE:> and <PATH> are optional. The <PATH> is a string
1559 * of hook names separated by dots. This breaks out the original
1560 * string, setting *nodep to "NODE" (or NULL if none) and *pathp
1561 * to "PATH" (or NULL if degenerate). Also, *hookp will point to
1562 * the final hook component of <PATH>, if any, otherwise NULL.
1563 *
1564 * This returns -1 if the path is malformed. The char ** are optional.
1565 ***********************************************************************/
1566 int
1567 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp)
1568 {
1569 char *node, *path, *hook;
1570 int k;
1571
1572 /*
1573 * Extract absolute NODE, if any
1574 */
1575 for (path = addr; *path && *path != ':'; path++);
1576 if (*path) {
1577 node = addr; /* Here's the NODE */
1578 *path++ = '\0'; /* Here's the PATH */
1579
1580 /* Node name must not be empty */
1581 if (!*node)
1582 return -1;
1583
1584 /* A name of "." is OK; otherwise '.' not allowed */
1585 if (strcmp(node, ".") != 0) {
1586 for (k = 0; node[k]; k++)
1587 if (node[k] == '.')
1588 return -1;
1589 }
1590 } else {
1591 node = NULL; /* No absolute NODE */
1592 path = addr; /* Here's the PATH */
1593 }
1594
1595 /* Snoop for illegal characters in PATH */
1596 for (k = 0; path[k]; k++)
1597 if (path[k] == ':')
1598 return -1;
1599
1600 /* Check for no repeated dots in PATH */
1601 for (k = 0; path[k]; k++)
1602 if (path[k] == '.' && path[k + 1] == '.')
1603 return -1;
1604
1605 /* Remove extra (degenerate) dots from beginning or end of PATH */
1606 if (path[0] == '.')
1607 path++;
1608 if (*path && path[strlen(path) - 1] == '.')
1609 path[strlen(path) - 1] = 0;
1610
1611 /* If PATH has a dot, then we're not talking about a hook */
1612 if (*path) {
1613 for (hook = path, k = 0; path[k]; k++)
1614 if (path[k] == '.') {
1615 hook = NULL;
1616 break;
1617 }
1618 } else
1619 path = hook = NULL;
1620
1621 /* Done */
1622 if (nodep)
1623 *nodep = node;
1624 if (pathp)
1625 *pathp = path;
1626 if (hookp)
1627 *hookp = hook;
1628 return (0);
1629 }
1630
1631 /*
1632 * Given a path, which may be absolute or relative, and a starting node,
1633 * return the destination node.
1634 */
1635 int
1636 ng_path2noderef(node_p here, const char *address,
1637 node_p *destp, hook_p *lasthook)
1638 {
1639 char fullpath[NG_PATHSIZ];
1640 char *nodename, *path, pbuf[2];
1641 node_p node, oldnode;
1642 char *cp;
1643 hook_p hook = NULL;
1644
1645 /* Initialize */
1646 if (destp == NULL) {
1647 TRAP_ERROR();
1648 return EINVAL;
1649 }
1650 *destp = NULL;
1651
1652 /* Make a writable copy of address for ng_path_parse() */
1653 strncpy(fullpath, address, sizeof(fullpath) - 1);
1654 fullpath[sizeof(fullpath) - 1] = '\0';
1655
1656 /* Parse out node and sequence of hooks */
1657 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) {
1658 TRAP_ERROR();
1659 return EINVAL;
1660 }
1661 if (path == NULL) {
1662 pbuf[0] = '.'; /* Needs to be writable */
1663 pbuf[1] = '\0';
1664 path = pbuf;
1665 }
1666
1667 /*
1668 * For an absolute address, jump to the starting node.
1669 * Note that this holds a reference on the node for us.
1670 * Don't forget to drop the reference if we don't need it.
1671 */
1672 if (nodename) {
1673 node = ng_name2noderef(here, nodename);
1674 if (node == NULL) {
1675 TRAP_ERROR();
1676 return (ENOENT);
1677 }
1678 } else {
1679 if (here == NULL) {
1680 TRAP_ERROR();
1681 return (EINVAL);
1682 }
1683 node = here;
1684 NG_NODE_REF(node);
1685 }
1686
1687 /*
1688 * Now follow the sequence of hooks
1689 * XXX
1690 * We actually cannot guarantee that the sequence
1691 * is not being demolished as we crawl along it
1692 * without extra-ordinary locking etc.
1693 * So this is a bit dodgy to say the least.
1694 * We can probably hold up some things by holding
1695 * the nodelist mutex for the time of this
1696 * crawl if we wanted.. At least that way we wouldn't have to
1697 * worry about the nodes disappearing, but the hooks would still
1698 * be a problem.
1699 */
1700 for (cp = path; node != NULL && *cp != '\0'; ) {
1701 char *segment;
1702
1703 /*
1704 * Break out the next path segment. Replace the dot we just
1705 * found with a NUL; "cp" points to the next segment (or the
1706 * NUL at the end).
1707 */
1708 for (segment = cp; *cp != '\0'; cp++) {
1709 if (*cp == '.') {
1710 *cp++ = '\0';
1711 break;
1712 }
1713 }
1714
1715 /* Empty segment */
1716 if (*segment == '\0')
1717 continue;
1718
1719 /* We have a segment, so look for a hook by that name */
1720 hook = ng_findhook(node, segment);
1721
1722 /* Can't get there from here... */
1723 if (hook == NULL
1724 || NG_HOOK_PEER(hook) == NULL
1725 || NG_HOOK_NOT_VALID(hook)
1726 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) {
1727 TRAP_ERROR();
1728 NG_NODE_UNREF(node);
1729 #if 0
1730 printf("hooknotvalid %s %s %d %d %d %d ",
1731 path,
1732 segment,
1733 hook == NULL,
1734 NG_HOOK_PEER(hook) == NULL,
1735 NG_HOOK_NOT_VALID(hook),
1736 NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook)));
1737 #endif
1738 return (ENOENT);
1739 }
1740
1741 /*
1742 * Hop on over to the next node
1743 * XXX
1744 * Big race conditions here as hooks and nodes go away
1745 * *** Idea.. store an ng_ID_t in each hook and use that
1746 * instead of the direct hook in this crawl?
1747 */
1748 oldnode = node;
1749 if ((node = NG_PEER_NODE(hook)))
1750 NG_NODE_REF(node); /* XXX RACE */
1751 NG_NODE_UNREF(oldnode); /* XXX another race */
1752 if (NG_NODE_NOT_VALID(node)) {
1753 NG_NODE_UNREF(node); /* XXX more races */
1754 node = NULL;
1755 }
1756 }
1757
1758 /* If node somehow missing, fail here (probably this is not needed) */
1759 if (node == NULL) {
1760 TRAP_ERROR();
1761 return (ENXIO);
1762 }
1763
1764 /* Done */
1765 *destp = node;
1766 if (lasthook != NULL)
1767 *lasthook = (hook ? NG_HOOK_PEER(hook) : NULL);
1768 return (0);
1769 }
1770
1771 /***************************************************************\
1772 * Input queue handling.
1773 * All activities are submitted to the node via the input queue
1774 * which implements a multiple-reader/single-writer gate.
1775 * Items which cannot be handled immediately are queued.
1776 *
1777 * read-write queue locking inline functions *
1778 \***************************************************************/
1779
1780 static __inline item_p ng_dequeue(struct ng_queue * ngq, int *rw);
1781 static __inline item_p ng_acquire_read(struct ng_queue * ngq,
1782 item_p item);
1783 static __inline item_p ng_acquire_write(struct ng_queue * ngq,
1784 item_p item);
1785 static __inline void ng_leave_read(struct ng_queue * ngq);
1786 static __inline void ng_leave_write(struct ng_queue * ngq);
1787 static __inline void ng_queue_rw(struct ng_queue * ngq,
1788 item_p item, int rw);
1789
1790 /*
1791 * Definition of the bits fields in the ng_queue flag word.
1792 * Defined here rather than in netgraph.h because no-one should fiddle
1793 * with them.
1794 *
1795 * The ordering here may be important! don't shuffle these.
1796 */
1797 /*-
1798 Safety Barrier--------+ (adjustable to suit taste) (not used yet)
1799 |
1800 V
1801 +-------+-------+-------+-------+-------+-------+-------+-------+
1802 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
1803 | |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |P|A|
1804 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |O|W|
1805 +-------+-------+-------+-------+-------+-------+-------+-------+
1806 \___________________________ ____________________________/ | |
1807 V | |
1808 [active reader count] | |
1809 | |
1810 Operation Pending -------------------------------+ |
1811 |
1812 Active Writer ---------------------------------------+
1813
1814 Node queue has such semantics:
1815 - All flags modifications are atomic.
1816 - Reader count can be incremented only if there is no writer or pending flags.
1817 As soon as this can't be done with single operation, it is implemented with
1818 spin loop and atomic_cmpset().
1819 - Writer flag can be set only if there is no any bits set.
1820 It is implemented with atomic_cmpset().
1821 - Pending flag can be set any time, but to avoid collision on queue processing
1822 all queue fields are protected by the mutex.
1823 - Queue processing thread reads queue holding the mutex, but releases it while
1824 processing. When queue is empty pending flag is removed.
1825 */
1826
1827 #define WRITER_ACTIVE 0x00000001
1828 #define OP_PENDING 0x00000002
1829 #define READER_INCREMENT 0x00000004
1830 #define READER_MASK 0xfffffffc /* Not valid if WRITER_ACTIVE is set */
1831 #define SAFETY_BARRIER 0x00100000 /* 128K items queued should be enough */
1832
1833 /* Defines of more elaborate states on the queue */
1834 /* Mask of bits a new read cares about */
1835 #define NGQ_RMASK (WRITER_ACTIVE|OP_PENDING)
1836
1837 /* Mask of bits a new write cares about */
1838 #define NGQ_WMASK (NGQ_RMASK|READER_MASK)
1839
1840 /* Test to decide if there is something on the queue. */
1841 #define QUEUE_ACTIVE(QP) ((QP)->q_flags & OP_PENDING)
1842
1843 /* How to decide what the next queued item is. */
1844 #define HEAD_IS_READER(QP) NGI_QUEUED_READER((QP)->queue)
1845 #define HEAD_IS_WRITER(QP) NGI_QUEUED_WRITER((QP)->queue) /* notused */
1846
1847 /* Read the status to decide if the next item on the queue can now run. */
1848 #define QUEUED_READER_CAN_PROCEED(QP) \
1849 (((QP)->q_flags & (NGQ_RMASK & ~OP_PENDING)) == 0)
1850 #define QUEUED_WRITER_CAN_PROCEED(QP) \
1851 (((QP)->q_flags & (NGQ_WMASK & ~OP_PENDING)) == 0)
1852
1853 /* Is there a chance of getting ANY work off the queue? */
1854 #define NEXT_QUEUED_ITEM_CAN_PROCEED(QP) \
1855 ((HEAD_IS_READER(QP)) ? QUEUED_READER_CAN_PROCEED(QP) : \
1856 QUEUED_WRITER_CAN_PROCEED(QP))
1857
1858
1859 #define NGQRW_R 0
1860 #define NGQRW_W 1
1861
1862 /*
1863 * Taking into account the current state of the queue and node, possibly take
1864 * the next entry off the queue and return it. Return NULL if there was
1865 * nothing we could return, either because there really was nothing there, or
1866 * because the node was in a state where it cannot yet process the next item
1867 * on the queue.
1868 */
1869 static __inline item_p
1870 ng_dequeue(struct ng_queue *ngq, int *rw)
1871 {
1872 item_p item;
1873
1874 /* This MUST be called with the mutex held. */
1875 mtx_assert(&ngq->q_mtx, MA_OWNED);
1876
1877 /* If there is nothing queued, then just return. */
1878 if (!QUEUE_ACTIVE(ngq)) {
1879 CTR4(KTR_NET, "%20s: node [%x] (%p) queue empty; "
1880 "queue flags 0x%lx", __func__,
1881 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags);
1882 return (NULL);
1883 }
1884
1885 /*
1886 * From here, we can assume there is a head item.
1887 * We need to find out what it is and if it can be dequeued, given
1888 * the current state of the node.
1889 */
1890 if (HEAD_IS_READER(ngq)) {
1891 while (1) {
1892 long t = ngq->q_flags;
1893 if (t & WRITER_ACTIVE) {
1894 /* There is writer, reader can't proceed. */
1895 CTR4(KTR_NET, "%20s: node [%x] (%p) queued reader "
1896 "can't proceed; queue flags 0x%lx", __func__,
1897 ngq->q_node->nd_ID, ngq->q_node, t);
1898 return (NULL);
1899 }
1900 if (atomic_cmpset_acq_long(&ngq->q_flags, t,
1901 t + READER_INCREMENT))
1902 break;
1903 cpu_spinwait();
1904 }
1905 /* We have got reader lock for the node. */
1906 *rw = NGQRW_R;
1907 } else if (atomic_cmpset_acq_long(&ngq->q_flags, OP_PENDING,
1908 OP_PENDING + WRITER_ACTIVE)) {
1909 /* We have got writer lock for the node. */
1910 *rw = NGQRW_W;
1911 } else {
1912 /* There is somebody other, writer can't proceed. */
1913 CTR4(KTR_NET, "%20s: node [%x] (%p) queued writer "
1914 "can't proceed; queue flags 0x%lx", __func__,
1915 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags);
1916 return (NULL);
1917 }
1918
1919 /*
1920 * Now we dequeue the request (whatever it may be) and correct the
1921 * pending flags and the next and last pointers.
1922 */
1923 item = ngq->queue;
1924 ngq->queue = item->el_next;
1925 if (ngq->last == &(item->el_next)) {
1926 ngq->last = &(ngq->queue);
1927 atomic_clear_long(&ngq->q_flags, OP_PENDING);
1928 }
1929 CTR6(KTR_NET, "%20s: node [%x] (%p) returning item %p as %s; "
1930 "queue flags 0x%lx", __func__,
1931 ngq->q_node->nd_ID, ngq->q_node, item, *rw ? "WRITER" : "READER" ,
1932 ngq->q_flags);
1933 return (item);
1934 }
1935
1936 /*
1937 * Queue a packet to be picked up later by someone else.
1938 * If the queue could be run now, add node to the queue handler's worklist.
1939 */
1940 static __inline void
1941 ng_queue_rw(struct ng_queue * ngq, item_p item, int rw)
1942 {
1943 if (rw == NGQRW_W)
1944 NGI_SET_WRITER(item);
1945 else
1946 NGI_SET_READER(item);
1947 item->el_next = NULL; /* maybe not needed */
1948
1949 NG_QUEUE_LOCK(ngq);
1950 /* Set OP_PENDING flag and enqueue the item. */
1951 atomic_set_long(&ngq->q_flags, OP_PENDING);
1952 *ngq->last = item;
1953 ngq->last = &(item->el_next);
1954
1955 CTR5(KTR_NET, "%20s: node [%x] (%p) queued item %p as %s", __func__,
1956 ngq->q_node->nd_ID, ngq->q_node, item, rw ? "WRITER" : "READER" );
1957
1958 /*
1959 * We can take the worklist lock with the node locked
1960 * BUT NOT THE REVERSE!
1961 */
1962 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
1963 ng_worklist_add(ngq->q_node);
1964 NG_QUEUE_UNLOCK(ngq);
1965 }
1966
1967 /* Acquire reader lock on node. If node is busy, queue the packet. */
1968 static __inline item_p
1969 ng_acquire_read(struct ng_queue *ngq, item_p item)
1970 {
1971 KASSERT(ngq != &ng_deadnode.nd_input_queue,
1972 ("%s: working on deadnode", __func__));
1973
1974 /* Reader needs node without writer and pending items. */
1975 while (1) {
1976 long t = ngq->q_flags;
1977 if (t & NGQ_RMASK)
1978 break; /* Node is not ready for reader. */
1979 if (atomic_cmpset_acq_long(&ngq->q_flags, t, t + READER_INCREMENT)) {
1980 /* Successfully grabbed node */
1981 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p",
1982 __func__, ngq->q_node->nd_ID, ngq->q_node, item);
1983 return (item);
1984 }
1985 cpu_spinwait();
1986 };
1987
1988 /* Queue the request for later. */
1989 ng_queue_rw(ngq, item, NGQRW_R);
1990
1991 return (NULL);
1992 }
1993
1994 /* Acquire writer lock on node. If node is busy, queue the packet. */
1995 static __inline item_p
1996 ng_acquire_write(struct ng_queue *ngq, item_p item)
1997 {
1998 KASSERT(ngq != &ng_deadnode.nd_input_queue,
1999 ("%s: working on deadnode", __func__));
2000
2001 /* Writer needs completely idle node. */
2002 if (atomic_cmpset_acq_long(&ngq->q_flags, 0, WRITER_ACTIVE)) {
2003 /* Successfully grabbed node */
2004 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p",
2005 __func__, ngq->q_node->nd_ID, ngq->q_node, item);
2006 return (item);
2007 }
2008
2009 /* Queue the request for later. */
2010 ng_queue_rw(ngq, item, NGQRW_W);
2011
2012 return (NULL);
2013 }
2014
2015 #if 0
2016 static __inline item_p
2017 ng_upgrade_write(struct ng_queue *ngq, item_p item)
2018 {
2019 KASSERT(ngq != &ng_deadnode.nd_input_queue,
2020 ("%s: working on deadnode", __func__));
2021
2022 NGI_SET_WRITER(item);
2023
2024 mtx_lock_spin(&(ngq->q_mtx));
2025
2026 /*
2027 * There will never be no readers as we are there ourselves.
2028 * Set the WRITER_ACTIVE flags ASAP to block out fast track readers.
2029 * The caller we are running from will call ng_leave_read()
2030 * soon, so we must account for that. We must leave again with the
2031 * READER lock. If we find other readers, then
2032 * queue the request for later. However "later" may be rignt now
2033 * if there are no readers. We don't really care if there are queued
2034 * items as we will bypass them anyhow.
2035 */
2036 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE - READER_INCREMENT);
2037 if (ngq->q_flags & (NGQ_WMASK & ~OP_PENDING) == WRITER_ACTIVE) {
2038 mtx_unlock_spin(&(ngq->q_mtx));
2039
2040 /* It's just us, act on the item. */
2041 /* will NOT drop writer lock when done */
2042 ng_apply_item(node, item, 0);
2043
2044 /*
2045 * Having acted on the item, atomically
2046 * down grade back to READER and finish up
2047 */
2048 atomic_add_long(&ngq->q_flags,
2049 READER_INCREMENT - WRITER_ACTIVE);
2050
2051 /* Our caller will call ng_leave_read() */
2052 return;
2053 }
2054 /*
2055 * It's not just us active, so queue us AT THE HEAD.
2056 * "Why?" I hear you ask.
2057 * Put us at the head of the queue as we've already been
2058 * through it once. If there is nothing else waiting,
2059 * set the correct flags.
2060 */
2061 if ((item->el_next = ngq->queue) == NULL) {
2062 /*
2063 * Set up the "last" pointer.
2064 * We are the only (and thus last) item
2065 */
2066 ngq->last = &(item->el_next);
2067
2068 /* We've gone from, 0 to 1 item in the queue */
2069 atomic_set_long(&ngq->q_flags, OP_PENDING);
2070
2071 CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__,
2072 ngq->q_node->nd_ID, ngq->q_node);
2073 };
2074 ngq->queue = item;
2075 CTR5(KTR_NET, "%20s: node [%x] (%p) requeued item %p as WRITER",
2076 __func__, ngq->q_node->nd_ID, ngq->q_node, item );
2077
2078 /* Reverse what we did above. That downgrades us back to reader */
2079 atomic_add_long(&ngq->q_flags, READER_INCREMENT - WRITER_ACTIVE);
2080 if (QUEUE_ACTIVE(ngq) && NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
2081 ng_worklist_add(ngq->q_node);
2082 mtx_unlock_spin(&(ngq->q_mtx));
2083
2084 return;
2085 }
2086
2087 #endif
2088
2089 /* Release reader lock. */
2090 static __inline void
2091 ng_leave_read(struct ng_queue *ngq)
2092 {
2093 atomic_subtract_rel_long(&ngq->q_flags, READER_INCREMENT);
2094 }
2095
2096 /* Release writer lock. */
2097 static __inline void
2098 ng_leave_write(struct ng_queue *ngq)
2099 {
2100 atomic_clear_rel_long(&ngq->q_flags, WRITER_ACTIVE);
2101 }
2102
2103 /* Purge node queue. Called on node shutdown. */
2104 static void
2105 ng_flush_input_queue(struct ng_queue * ngq)
2106 {
2107 item_p item;
2108
2109 NG_QUEUE_LOCK(ngq);
2110 while (ngq->queue) {
2111 item = ngq->queue;
2112 ngq->queue = item->el_next;
2113 if (ngq->last == &(item->el_next)) {
2114 ngq->last = &(ngq->queue);
2115 atomic_clear_long(&ngq->q_flags, OP_PENDING);
2116 }
2117 NG_QUEUE_UNLOCK(ngq);
2118
2119 /* If the item is supplying a callback, call it with an error */
2120 if (item->apply != NULL) {
2121 if (item->depth == 1)
2122 item->apply->error = ENOENT;
2123 if (refcount_release(&item->apply->refs)) {
2124 (*item->apply->apply)(item->apply->context,
2125 item->apply->error);
2126 }
2127 }
2128 NG_FREE_ITEM(item);
2129 NG_QUEUE_LOCK(ngq);
2130 }
2131 NG_QUEUE_UNLOCK(ngq);
2132 }
2133
2134 /***********************************************************************
2135 * Externally visible method for sending or queueing messages or data.
2136 ***********************************************************************/
2137
2138 /*
2139 * The module code should have filled out the item correctly by this stage:
2140 * Common:
2141 * reference to destination node.
2142 * Reference to destination rcv hook if relevant.
2143 * apply pointer must be or NULL or reference valid struct ng_apply_info.
2144 * Data:
2145 * pointer to mbuf
2146 * Control_Message:
2147 * pointer to msg.
2148 * ID of original sender node. (return address)
2149 * Function:
2150 * Function pointer
2151 * void * argument
2152 * integer argument
2153 *
2154 * The nodes have several routines and macros to help with this task:
2155 */
2156
2157 int
2158 ng_snd_item(item_p item, int flags)
2159 {
2160 hook_p hook;
2161 node_p node;
2162 int queue, rw;
2163 struct ng_queue *ngq;
2164 int error = 0;
2165
2166 /* We are sending item, so it must be present! */
2167 KASSERT(item != NULL, ("ng_snd_item: item is NULL"));
2168
2169 #ifdef NETGRAPH_DEBUG
2170 _ngi_check(item, __FILE__, __LINE__);
2171 #endif
2172
2173 /* Item was sent once more, postpone apply() call. */
2174 if (item->apply)
2175 refcount_acquire(&item->apply->refs);
2176
2177 node = NGI_NODE(item);
2178 /* Node is never optional. */
2179 KASSERT(node != NULL, ("ng_snd_item: node is NULL"));
2180
2181 hook = NGI_HOOK(item);
2182 /* Valid hook and mbuf are mandatory for data. */
2183 if ((item->el_flags & NGQF_TYPE) == NGQF_DATA) {
2184 KASSERT(hook != NULL, ("ng_snd_item: hook for data is NULL"));
2185 if (NGI_M(item) == NULL)
2186 ERROUT(EINVAL);
2187 CHECK_DATA_MBUF(NGI_M(item));
2188 }
2189
2190 /*
2191 * If the item or the node specifies single threading, force
2192 * writer semantics. Similarly, the node may say one hook always
2193 * produces writers. These are overrides.
2194 */
2195 if (((item->el_flags & NGQF_RW) == NGQF_WRITER) ||
2196 (node->nd_flags & NGF_FORCE_WRITER) ||
2197 (hook && (hook->hk_flags & HK_FORCE_WRITER))) {
2198 rw = NGQRW_W;
2199 } else {
2200 rw = NGQRW_R;
2201 }
2202
2203 /*
2204 * If sender or receiver requests queued delivery or stack usage
2205 * level is dangerous - enqueue message.
2206 */
2207 if ((flags & NG_QUEUE) || (hook && (hook->hk_flags & HK_QUEUE))) {
2208 queue = 1;
2209 } else {
2210 queue = 0;
2211 #ifdef GET_STACK_USAGE
2212 /*
2213 * Most of netgraph nodes have small stack consumption and
2214 * for them 25% of free stack space is more than enough.
2215 * Nodes/hooks with higher stack usage should be marked as
2216 * HI_STACK. For them 50% of stack will be guaranteed then.
2217 * XXX: Values 25% and 50% are completely empirical.
2218 */
2219 size_t st, su, sl;
2220 GET_STACK_USAGE(st, su);
2221 sl = st - su;
2222 if ((sl * 4 < st) ||
2223 ((sl * 2 < st) && ((node->nd_flags & NGF_HI_STACK) ||
2224 (hook && (hook->hk_flags & HK_HI_STACK))))) {
2225 queue = 1;
2226 }
2227 #endif
2228 }
2229
2230 ngq = &node->nd_input_queue;
2231 if (queue) {
2232 item->depth = 1;
2233 /* Put it on the queue for that node*/
2234 ng_queue_rw(ngq, item, rw);
2235 return ((flags & NG_PROGRESS) ? EINPROGRESS : 0);
2236 }
2237
2238 /*
2239 * We already decided how we will be queueud or treated.
2240 * Try get the appropriate operating permission.
2241 */
2242 if (rw == NGQRW_R)
2243 item = ng_acquire_read(ngq, item);
2244 else
2245 item = ng_acquire_write(ngq, item);
2246
2247 /* Item was queued while trying to get permission. */
2248 if (item == NULL)
2249 return ((flags & NG_PROGRESS) ? EINPROGRESS : 0);
2250
2251 NGI_GET_NODE(item, node); /* zaps stored node */
2252
2253 item->depth++;
2254 error = ng_apply_item(node, item, rw); /* drops r/w lock when done */
2255
2256 /* If something is waiting on queue and ready, schedule it. */
2257 if (QUEUE_ACTIVE(ngq)) {
2258 NG_QUEUE_LOCK(ngq);
2259 if (QUEUE_ACTIVE(ngq) && NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
2260 ng_worklist_add(ngq->q_node);
2261 NG_QUEUE_UNLOCK(ngq);
2262 }
2263
2264 /*
2265 * Node may go away as soon as we remove the reference.
2266 * Whatever we do, DO NOT access the node again!
2267 */
2268 NG_NODE_UNREF(node);
2269
2270 return (error);
2271
2272 done:
2273 /* If was not sent, apply callback here. */
2274 if (item->apply != NULL) {
2275 if (item->depth == 0 && error != 0)
2276 item->apply->error = error;
2277 if (refcount_release(&item->apply->refs)) {
2278 (*item->apply->apply)(item->apply->context,
2279 item->apply->error);
2280 }
2281 }
2282
2283 NG_FREE_ITEM(item);
2284 return (error);
2285 }
2286
2287 /*
2288 * We have an item that was possibly queued somewhere.
2289 * It should contain all the information needed
2290 * to run it on the appropriate node/hook.
2291 * If there is apply pointer and we own the last reference, call apply().
2292 */
2293 static int
2294 ng_apply_item(node_p node, item_p item, int rw)
2295 {
2296 hook_p hook;
2297 ng_rcvdata_t *rcvdata;
2298 ng_rcvmsg_t *rcvmsg;
2299 struct ng_apply_info *apply;
2300 int error = 0, depth;
2301
2302 /* Node and item are never optional. */
2303 KASSERT(node != NULL, ("ng_apply_item: node is NULL"));
2304 KASSERT(item != NULL, ("ng_apply_item: item is NULL"));
2305
2306 NGI_GET_HOOK(item, hook); /* clears stored hook */
2307 #ifdef NETGRAPH_DEBUG
2308 _ngi_check(item, __FILE__, __LINE__);
2309 #endif
2310
2311 apply = item->apply;
2312 depth = item->depth;
2313
2314 switch (item->el_flags & NGQF_TYPE) {
2315 case NGQF_DATA:
2316 /*
2317 * Check things are still ok as when we were queued.
2318 */
2319 KASSERT(hook != NULL, ("ng_apply_item: hook for data is NULL"));
2320 if (NG_HOOK_NOT_VALID(hook) ||
2321 NG_NODE_NOT_VALID(node)) {
2322 error = EIO;
2323 NG_FREE_ITEM(item);
2324 break;
2325 }
2326 /*
2327 * If no receive method, just silently drop it.
2328 * Give preference to the hook over-ride method
2329 */
2330 if ((!(rcvdata = hook->hk_rcvdata))
2331 && (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) {
2332 error = 0;
2333 NG_FREE_ITEM(item);
2334 break;
2335 }
2336 error = (*rcvdata)(hook, item);
2337 break;
2338 case NGQF_MESG:
2339 if (hook && NG_HOOK_NOT_VALID(hook)) {
2340 /*
2341 * The hook has been zapped then we can't use it.
2342 * Immediately drop its reference.
2343 * The message may not need it.
2344 */
2345 NG_HOOK_UNREF(hook);
2346 hook = NULL;
2347 }
2348 /*
2349 * Similarly, if the node is a zombie there is
2350 * nothing we can do with it, drop everything.
2351 */
2352 if (NG_NODE_NOT_VALID(node)) {
2353 TRAP_ERROR();
2354 error = EINVAL;
2355 NG_FREE_ITEM(item);
2356 break;
2357 }
2358 /*
2359 * Call the appropriate message handler for the object.
2360 * It is up to the message handler to free the message.
2361 * If it's a generic message, handle it generically,
2362 * otherwise call the type's message handler (if it exists).
2363 * XXX (race). Remember that a queued message may
2364 * reference a node or hook that has just been
2365 * invalidated. It will exist as the queue code
2366 * is holding a reference, but..
2367 */
2368 if ((NGI_MSG(item)->header.typecookie == NGM_GENERIC_COOKIE) &&
2369 ((NGI_MSG(item)->header.flags & NGF_RESP) == 0)) {
2370 error = ng_generic_msg(node, item, hook);
2371 break;
2372 }
2373 if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg))) &&
2374 (!(rcvmsg = node->nd_type->rcvmsg))) {
2375 TRAP_ERROR();
2376 error = 0;
2377 NG_FREE_ITEM(item);
2378 break;
2379 }
2380 error = (*rcvmsg)(node, item, hook);
2381 break;
2382 case NGQF_FN:
2383 case NGQF_FN2:
2384 /*
2385 * In the case of the shutdown message we allow it to hit
2386 * even if the node is invalid.
2387 */
2388 if (NG_NODE_NOT_VALID(node) &&
2389 NGI_FN(item) != &ng_rmnode) {
2390 TRAP_ERROR();
2391 error = EINVAL;
2392 NG_FREE_ITEM(item);
2393 break;
2394 }
2395 /* Same is about some internal functions and invalid hook. */
2396 if (hook && NG_HOOK_NOT_VALID(hook) &&
2397 NGI_FN2(item) != &ng_con_part2 &&
2398 NGI_FN2(item) != &ng_con_part3 &&
2399 NGI_FN(item) != &ng_rmhook_part2) {
2400 TRAP_ERROR();
2401 error = EINVAL;
2402 NG_FREE_ITEM(item);
2403 break;
2404 }
2405
2406 if ((item->el_flags & NGQF_TYPE) == NGQF_FN) {
2407 (*NGI_FN(item))(node, hook, NGI_ARG1(item),
2408 NGI_ARG2(item));
2409 NG_FREE_ITEM(item);
2410 } else /* it is NGQF_FN2 */
2411 error = (*NGI_FN2(item))(node, item, hook);
2412 break;
2413 }
2414 /*
2415 * We held references on some of the resources
2416 * that we took from the item. Now that we have
2417 * finished doing everything, drop those references.
2418 */
2419 if (hook)
2420 NG_HOOK_UNREF(hook);
2421
2422 if (rw == NGQRW_R)
2423 ng_leave_read(&node->nd_input_queue);
2424 else
2425 ng_leave_write(&node->nd_input_queue);
2426
2427 /* Apply callback. */
2428 if (apply != NULL) {
2429 if (depth == 1 && error != 0)
2430 apply->error = error;
2431 if (refcount_release(&apply->refs))
2432 (*apply->apply)(apply->context, apply->error);
2433 }
2434
2435 return (error);
2436 }
2437
2438 /***********************************************************************
2439 * Implement the 'generic' control messages
2440 ***********************************************************************/
2441 static int
2442 ng_generic_msg(node_p here, item_p item, hook_p lasthook)
2443 {
2444 int error = 0;
2445 struct ng_mesg *msg;
2446 struct ng_mesg *resp = NULL;
2447
2448 NGI_GET_MSG(item, msg);
2449 if (msg->header.typecookie != NGM_GENERIC_COOKIE) {
2450 TRAP_ERROR();
2451 error = EINVAL;
2452 goto out;
2453 }
2454 switch (msg->header.cmd) {
2455 case NGM_SHUTDOWN:
2456 ng_rmnode(here, NULL, NULL, 0);
2457 break;
2458 case NGM_MKPEER:
2459 {
2460 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data;
2461
2462 if (msg->header.arglen != sizeof(*mkp)) {
2463 TRAP_ERROR();
2464 error = EINVAL;
2465 break;
2466 }
2467 mkp->type[sizeof(mkp->type) - 1] = '\0';
2468 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0';
2469 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0';
2470 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type);
2471 break;
2472 }
2473 case NGM_CONNECT:
2474 {
2475 struct ngm_connect *const con =
2476 (struct ngm_connect *) msg->data;
2477 node_p node2;
2478
2479 if (msg->header.arglen != sizeof(*con)) {
2480 TRAP_ERROR();
2481 error = EINVAL;
2482 break;
2483 }
2484 con->path[sizeof(con->path) - 1] = '\0';
2485 con->ourhook[sizeof(con->ourhook) - 1] = '\0';
2486 con->peerhook[sizeof(con->peerhook) - 1] = '\0';
2487 /* Don't forget we get a reference.. */
2488 error = ng_path2noderef(here, con->path, &node2, NULL);
2489 if (error)
2490 break;
2491 error = ng_con_nodes(item, here, con->ourhook,
2492 node2, con->peerhook);
2493 NG_NODE_UNREF(node2);
2494 break;
2495 }
2496 case NGM_NAME:
2497 {
2498 struct ngm_name *const nam = (struct ngm_name *) msg->data;
2499
2500 if (msg->header.arglen != sizeof(*nam)) {
2501 TRAP_ERROR();
2502 error = EINVAL;
2503 break;
2504 }
2505 nam->name[sizeof(nam->name) - 1] = '\0';
2506 error = ng_name_node(here, nam->name);
2507 break;
2508 }
2509 case NGM_RMHOOK:
2510 {
2511 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data;
2512 hook_p hook;
2513
2514 if (msg->header.arglen != sizeof(*rmh)) {
2515 TRAP_ERROR();
2516 error = EINVAL;
2517 break;
2518 }
2519 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0';
2520 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL)
2521 ng_destroy_hook(hook);
2522 break;
2523 }
2524 case NGM_NODEINFO:
2525 {
2526 struct nodeinfo *ni;
2527
2528 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_NOWAIT);
2529 if (resp == NULL) {
2530 error = ENOMEM;
2531 break;
2532 }
2533
2534 /* Fill in node info */
2535 ni = (struct nodeinfo *) resp->data;
2536 if (NG_NODE_HAS_NAME(here))
2537 strcpy(ni->name, NG_NODE_NAME(here));
2538 strcpy(ni->type, here->nd_type->name);
2539 ni->id = ng_node2ID(here);
2540 ni->hooks = here->nd_numhooks;
2541 break;
2542 }
2543 case NGM_LISTHOOKS:
2544 {
2545 const int nhooks = here->nd_numhooks;
2546 struct hooklist *hl;
2547 struct nodeinfo *ni;
2548 hook_p hook;
2549
2550 /* Get response struct */
2551 NG_MKRESPONSE(resp, msg, sizeof(*hl)
2552 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT);
2553 if (resp == NULL) {
2554 error = ENOMEM;
2555 break;
2556 }
2557 hl = (struct hooklist *) resp->data;
2558 ni = &hl->nodeinfo;
2559
2560 /* Fill in node info */
2561 if (NG_NODE_HAS_NAME(here))
2562 strcpy(ni->name, NG_NODE_NAME(here));
2563 strcpy(ni->type, here->nd_type->name);
2564 ni->id = ng_node2ID(here);
2565
2566 /* Cycle through the linked list of hooks */
2567 ni->hooks = 0;
2568 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) {
2569 struct linkinfo *const link = &hl->link[ni->hooks];
2570
2571 if (ni->hooks >= nhooks) {
2572 log(LOG_ERR, "%s: number of %s changed\n",
2573 __func__, "hooks");
2574 break;
2575 }
2576 if (NG_HOOK_NOT_VALID(hook))
2577 continue;
2578 strcpy(link->ourhook, NG_HOOK_NAME(hook));
2579 strcpy(link->peerhook, NG_PEER_HOOK_NAME(hook));
2580 if (NG_PEER_NODE_NAME(hook)[0] != '\0')
2581 strcpy(link->nodeinfo.name,
2582 NG_PEER_NODE_NAME(hook));
2583 strcpy(link->nodeinfo.type,
2584 NG_PEER_NODE(hook)->nd_type->name);
2585 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook));
2586 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks;
2587 ni->hooks++;
2588 }
2589 break;
2590 }
2591
2592 case NGM_LISTNAMES:
2593 case NGM_LISTNODES:
2594 {
2595 const int unnamed = (msg->header.cmd == NGM_LISTNODES);
2596 struct namelist *nl;
2597 node_p node;
2598 int num = 0, i;
2599
2600 mtx_lock(&ng_namehash_mtx);
2601 /* Count number of nodes */
2602 for (i = 0; i < NG_NAME_HASH_SIZE; i++) {
2603 LIST_FOREACH(node, &ng_name_hash[i], nd_nodes) {
2604 if (NG_NODE_IS_VALID(node) &&
2605 (unnamed || NG_NODE_HAS_NAME(node))) {
2606 num++;
2607 }
2608 }
2609 }
2610 mtx_unlock(&ng_namehash_mtx);
2611
2612 /* Get response struct */
2613 NG_MKRESPONSE(resp, msg, sizeof(*nl)
2614 + (num * sizeof(struct nodeinfo)), M_NOWAIT);
2615 if (resp == NULL) {
2616 error = ENOMEM;
2617 break;
2618 }
2619 nl = (struct namelist *) resp->data;
2620
2621 /* Cycle through the linked list of nodes */
2622 nl->numnames = 0;
2623 mtx_lock(&ng_namehash_mtx);
2624 for (i = 0; i < NG_NAME_HASH_SIZE; i++) {
2625 LIST_FOREACH(node, &ng_name_hash[i], nd_nodes) {
2626 struct nodeinfo *const np =
2627 &nl->nodeinfo[nl->numnames];
2628
2629 if (NG_NODE_NOT_VALID(node))
2630 continue;
2631 if (!unnamed && (! NG_NODE_HAS_NAME(node)))
2632 continue;
2633 if (nl->numnames >= num) {
2634 log(LOG_ERR, "%s: number of nodes changed\n",
2635 __func__);
2636 break;
2637 }
2638 if (NG_NODE_HAS_NAME(node))
2639 strcpy(np->name, NG_NODE_NAME(node));
2640 strcpy(np->type, node->nd_type->name);
2641 np->id = ng_node2ID(node);
2642 np->hooks = node->nd_numhooks;
2643 nl->numnames++;
2644 }
2645 }
2646 mtx_unlock(&ng_namehash_mtx);
2647 break;
2648 }
2649
2650 case NGM_LISTTYPES:
2651 {
2652 struct typelist *tl;
2653 struct ng_type *type;
2654 int num = 0;
2655
2656 mtx_lock(&ng_typelist_mtx);
2657 /* Count number of types */
2658 LIST_FOREACH(type, &ng_typelist, types) {
2659 num++;
2660 }
2661 mtx_unlock(&ng_typelist_mtx);
2662
2663 /* Get response struct */
2664 NG_MKRESPONSE(resp, msg, sizeof(*tl)
2665 + (num * sizeof(struct typeinfo)), M_NOWAIT);
2666 if (resp == NULL) {
2667 error = ENOMEM;
2668 break;
2669 }
2670 tl = (struct typelist *) resp->data;
2671
2672 /* Cycle through the linked list of types */
2673 tl->numtypes = 0;
2674 mtx_lock(&ng_typelist_mtx);
2675 LIST_FOREACH(type, &ng_typelist, types) {
2676 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes];
2677
2678 if (tl->numtypes >= num) {
2679 log(LOG_ERR, "%s: number of %s changed\n",
2680 __func__, "types");
2681 break;
2682 }
2683 strcpy(tp->type_name, type->name);
2684 tp->numnodes = type->refs - 1; /* don't count list */
2685 tl->numtypes++;
2686 }
2687 mtx_unlock(&ng_typelist_mtx);
2688 break;
2689 }
2690
2691 case NGM_BINARY2ASCII:
2692 {
2693 int bufSize = 20 * 1024; /* XXX hard coded constant */
2694 const struct ng_parse_type *argstype;
2695 const struct ng_cmdlist *c;
2696 struct ng_mesg *binary, *ascii;
2697
2698 /* Data area must contain a valid netgraph message */
2699 binary = (struct ng_mesg *)msg->data;
2700 if (msg->header.arglen < sizeof(struct ng_mesg) ||
2701 (msg->header.arglen - sizeof(struct ng_mesg) <
2702 binary->header.arglen)) {
2703 TRAP_ERROR();
2704 error = EINVAL;
2705 break;
2706 }
2707
2708 /* Get a response message with lots of room */
2709 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_NOWAIT);
2710 if (resp == NULL) {
2711 error = ENOMEM;
2712 break;
2713 }
2714 ascii = (struct ng_mesg *)resp->data;
2715
2716 /* Copy binary message header to response message payload */
2717 bcopy(binary, ascii, sizeof(*binary));
2718
2719 /* Find command by matching typecookie and command number */
2720 for (c = here->nd_type->cmdlist;
2721 c != NULL && c->name != NULL; c++) {
2722 if (binary->header.typecookie == c->cookie
2723 && binary->header.cmd == c->cmd)
2724 break;
2725 }
2726 if (c == NULL || c->name == NULL) {
2727 for (c = ng_generic_cmds; c->name != NULL; c++) {
2728 if (binary->header.typecookie == c->cookie
2729 && binary->header.cmd == c->cmd)
2730 break;
2731 }
2732 if (c->name == NULL) {
2733 NG_FREE_MSG(resp);
2734 error = ENOSYS;
2735 break;
2736 }
2737 }
2738
2739 /* Convert command name to ASCII */
2740 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr),
2741 "%s", c->name);
2742
2743 /* Convert command arguments to ASCII */
2744 argstype = (binary->header.flags & NGF_RESP) ?
2745 c->respType : c->mesgType;
2746 if (argstype == NULL) {
2747 *ascii->data = '\0';
2748 } else {
2749 if ((error = ng_unparse(argstype,
2750 (u_char *)binary->data,
2751 ascii->data, bufSize)) != 0) {
2752 NG_FREE_MSG(resp);
2753 break;
2754 }
2755 }
2756
2757 /* Return the result as struct ng_mesg plus ASCII string */
2758 bufSize = strlen(ascii->data) + 1;
2759 ascii->header.arglen = bufSize;
2760 resp->header.arglen = sizeof(*ascii) + bufSize;
2761 break;
2762 }
2763
2764 case NGM_ASCII2BINARY:
2765 {
2766 int bufSize = 2000; /* XXX hard coded constant */
2767 const struct ng_cmdlist *c;
2768 const struct ng_parse_type *argstype;
2769 struct ng_mesg *ascii, *binary;
2770 int off = 0;
2771
2772 /* Data area must contain at least a struct ng_mesg + '\0' */
2773 ascii = (struct ng_mesg *)msg->data;
2774 if ((msg->header.arglen < sizeof(*ascii) + 1) ||
2775 (ascii->header.arglen < 1) ||
2776 (msg->header.arglen < sizeof(*ascii) +
2777 ascii->header.arglen)) {
2778 TRAP_ERROR();
2779 error = EINVAL;
2780 break;
2781 }
2782 ascii->data[ascii->header.arglen - 1] = '\0';
2783
2784 /* Get a response message with lots of room */
2785 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_NOWAIT);
2786 if (resp == NULL) {
2787 error = ENOMEM;
2788 break;
2789 }
2790 binary = (struct ng_mesg *)resp->data;
2791
2792 /* Copy ASCII message header to response message payload */
2793 bcopy(ascii, binary, sizeof(*ascii));
2794
2795 /* Find command by matching ASCII command string */
2796 for (c = here->nd_type->cmdlist;
2797 c != NULL && c->name != NULL; c++) {
2798 if (strcmp(ascii->header.cmdstr, c->name) == 0)
2799 break;
2800 }
2801 if (c == NULL || c->name == NULL) {
2802 for (c = ng_generic_cmds; c->name != NULL; c++) {
2803 if (strcmp(ascii->header.cmdstr, c->name) == 0)
2804 break;
2805 }
2806 if (c->name == NULL) {
2807 NG_FREE_MSG(resp);
2808 error = ENOSYS;
2809 break;
2810 }
2811 }
2812
2813 /* Convert command name to binary */
2814 binary->header.cmd = c->cmd;
2815 binary->header.typecookie = c->cookie;
2816
2817 /* Convert command arguments to binary */
2818 argstype = (binary->header.flags & NGF_RESP) ?
2819 c->respType : c->mesgType;
2820 if (argstype == NULL) {
2821 bufSize = 0;
2822 } else {
2823 if ((error = ng_parse(argstype, ascii->data,
2824 &off, (u_char *)binary->data, &bufSize)) != 0) {
2825 NG_FREE_MSG(resp);
2826 break;
2827 }
2828 }
2829
2830 /* Return the result */
2831 binary->header.arglen = bufSize;
2832 resp->header.arglen = sizeof(*binary) + bufSize;
2833 break;
2834 }
2835
2836 case NGM_TEXT_CONFIG:
2837 case NGM_TEXT_STATUS:
2838 /*
2839 * This one is tricky as it passes the command down to the
2840 * actual node, even though it is a generic type command.
2841 * This means we must assume that the item/msg is already freed
2842 * when control passes back to us.
2843 */
2844 if (here->nd_type->rcvmsg != NULL) {
2845 NGI_MSG(item) = msg; /* put it back as we found it */
2846 return((*here->nd_type->rcvmsg)(here, item, lasthook));
2847 }
2848 /* Fall through if rcvmsg not supported */
2849 default:
2850 TRAP_ERROR();
2851 error = EINVAL;
2852 }
2853 /*
2854 * Sometimes a generic message may be statically allocated
2855 * to avoid problems with allocating when in tight memeory situations.
2856 * Don't free it if it is so.
2857 * I break them appart here, because erros may cause a free if the item
2858 * in which case we'd be doing it twice.
2859 * they are kept together above, to simplify freeing.
2860 */
2861 out:
2862 NG_RESPOND_MSG(error, here, item, resp);
2863 NG_FREE_MSG(msg);
2864 return (error);
2865 }
2866
2867 /************************************************************************
2868 Queue element get/free routines
2869 ************************************************************************/
2870
2871 uma_zone_t ng_qzone;
2872 uma_zone_t ng_qdzone;
2873 static int numthreads = 0; /* number of queue threads */
2874 static int maxalloc = 4096;/* limit the damage of a leak */
2875 static int maxdata = 512; /* limit the damage of a DoS */
2876
2877 TUNABLE_INT("net.graph.threads", &numthreads);
2878 SYSCTL_INT(_net_graph, OID_AUTO, threads, CTLFLAG_RDTUN, &numthreads,
2879 0, "Number of queue processing threads to create");
2880 TUNABLE_INT("net.graph.maxalloc", &maxalloc);
2881 SYSCTL_INT(_net_graph, OID_AUTO, maxalloc, CTLFLAG_RDTUN, &maxalloc,
2882 0, "Maximum number of non-data queue items to allocate");
2883 TUNABLE_INT("net.graph.maxdata", &maxdata);
2884 SYSCTL_INT(_net_graph, OID_AUTO, maxdata, CTLFLAG_RDTUN, &maxdata,
2885 0, "Maximum number of data queue items to allocate");
2886
2887 #ifdef NETGRAPH_DEBUG
2888 static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist);
2889 static int allocated; /* number of items malloc'd */
2890 #endif
2891
2892 /*
2893 * Get a queue entry.
2894 * This is usually called when a packet first enters netgraph.
2895 * By definition, this is usually from an interrupt, or from a user.
2896 * Users are not so important, but try be quick for the times that it's
2897 * an interrupt.
2898 */
2899 static __inline item_p
2900 ng_alloc_item(int type, int flags)
2901 {
2902 item_p item;
2903
2904 KASSERT(((type & ~NGQF_TYPE) == 0),
2905 ("%s: incorrect item type: %d", __func__, type));
2906
2907 item = uma_zalloc((type == NGQF_DATA)?ng_qdzone:ng_qzone,
2908 ((flags & NG_WAITOK) ? M_WAITOK : M_NOWAIT) | M_ZERO);
2909
2910 if (item) {
2911 item->el_flags = type;
2912 #ifdef NETGRAPH_DEBUG
2913 mtx_lock(&ngq_mtx);
2914 TAILQ_INSERT_TAIL(&ng_itemlist, item, all);
2915 allocated++;
2916 mtx_unlock(&ngq_mtx);
2917 #endif
2918 }
2919
2920 return (item);
2921 }
2922
2923 /*
2924 * Release a queue entry
2925 */
2926 void
2927 ng_free_item(item_p item)
2928 {
2929 /*
2930 * The item may hold resources on it's own. We need to free
2931 * these before we can free the item. What they are depends upon
2932 * what kind of item it is. it is important that nodes zero
2933 * out pointers to resources that they remove from the item
2934 * or we release them again here.
2935 */
2936 switch (item->el_flags & NGQF_TYPE) {
2937 case NGQF_DATA:
2938 /* If we have an mbuf still attached.. */
2939 NG_FREE_M(_NGI_M(item));
2940 break;
2941 case NGQF_MESG:
2942 _NGI_RETADDR(item) = 0;
2943 NG_FREE_MSG(_NGI_MSG(item));
2944 break;
2945 case NGQF_FN:
2946 case NGQF_FN2:
2947 /* nothing to free really, */
2948 _NGI_FN(item) = NULL;
2949 _NGI_ARG1(item) = NULL;
2950 _NGI_ARG2(item) = 0;
2951 break;
2952 }
2953 /* If we still have a node or hook referenced... */
2954 _NGI_CLR_NODE(item);
2955 _NGI_CLR_HOOK(item);
2956
2957 #ifdef NETGRAPH_DEBUG
2958 mtx_lock(&ngq_mtx);
2959 TAILQ_REMOVE(&ng_itemlist, item, all);
2960 allocated--;
2961 mtx_unlock(&ngq_mtx);
2962 #endif
2963 uma_zfree(((item->el_flags & NGQF_TYPE) == NGQF_DATA)?
2964 ng_qdzone:ng_qzone, item);
2965 }
2966
2967 /*
2968 * Change type of the queue entry.
2969 * Possibly reallocates it from another UMA zone.
2970 */
2971 static __inline item_p
2972 ng_realloc_item(item_p pitem, int type, int flags)
2973 {
2974 item_p item;
2975 int from, to;
2976
2977 KASSERT((pitem != NULL), ("%s: can't reallocate NULL", __func__));
2978 KASSERT(((type & ~NGQF_TYPE) == 0),
2979 ("%s: incorrect item type: %d", __func__, type));
2980
2981 from = ((pitem->el_flags & NGQF_TYPE) == NGQF_DATA);
2982 to = (type == NGQF_DATA);
2983 if (from != to) {
2984 /* If reallocation is required do it and copy item. */
2985 if ((item = ng_alloc_item(type, flags)) == NULL) {
2986 ng_free_item(pitem);
2987 return (NULL);
2988 }
2989 *item = *pitem;
2990 ng_free_item(pitem);
2991 } else
2992 item = pitem;
2993 item->el_flags = (item->el_flags & ~NGQF_TYPE) | type;
2994
2995 return (item);
2996 }
2997
2998 /************************************************************************
2999 Module routines
3000 ************************************************************************/
3001
3002 /*
3003 * Handle the loading/unloading of a netgraph node type module
3004 */
3005 int
3006 ng_mod_event(module_t mod, int event, void *data)
3007 {
3008 struct ng_type *const type = data;
3009 int s, error = 0;
3010
3011 switch (event) {
3012 case MOD_LOAD:
3013
3014 /* Register new netgraph node type */
3015 s = splnet();
3016 if ((error = ng_newtype(type)) != 0) {
3017 splx(s);
3018 break;
3019 }
3020
3021 /* Call type specific code */
3022 if (type->mod_event != NULL)
3023 if ((error = (*type->mod_event)(mod, event, data))) {
3024 mtx_lock(&ng_typelist_mtx);
3025 type->refs--; /* undo it */
3026 LIST_REMOVE(type, types);
3027 mtx_unlock(&ng_typelist_mtx);
3028 }
3029 splx(s);
3030 break;
3031
3032 case MOD_UNLOAD:
3033 s = splnet();
3034 if (type->refs > 1) { /* make sure no nodes exist! */
3035 error = EBUSY;
3036 } else {
3037 if (type->refs == 0) {
3038 /* failed load, nothing to undo */
3039 splx(s);
3040 break;
3041 }
3042 if (type->mod_event != NULL) { /* check with type */
3043 error = (*type->mod_event)(mod, event, data);
3044 if (error != 0) { /* type refuses.. */
3045 splx(s);
3046 break;
3047 }
3048 }
3049 mtx_lock(&ng_typelist_mtx);
3050 LIST_REMOVE(type, types);
3051 mtx_unlock(&ng_typelist_mtx);
3052 }
3053 splx(s);
3054 break;
3055
3056 default:
3057 if (type->mod_event != NULL)
3058 error = (*type->mod_event)(mod, event, data);
3059 else
3060 error = EOPNOTSUPP; /* XXX ? */
3061 break;
3062 }
3063 return (error);
3064 }
3065
3066 /*
3067 * Handle loading and unloading for this code.
3068 * The only thing we need to link into is the NETISR strucure.
3069 */
3070 static int
3071 ngb_mod_event(module_t mod, int event, void *data)
3072 {
3073 int i, error = 0;
3074
3075 switch (event) {
3076 case MOD_LOAD:
3077 /* Initialize everything. */
3078 NG_WORKLIST_LOCK_INIT();
3079 mtx_init(&ng_typelist_mtx, "netgraph types mutex", NULL,
3080 MTX_DEF);
3081 mtx_init(&ng_idhash_mtx, "netgraph idhash mutex", NULL,
3082 MTX_DEF);
3083 mtx_init(&ng_namehash_mtx, "netgraph namehash mutex", NULL,
3084 MTX_DEF);
3085 mtx_init(&ng_topo_mtx, "netgraph topology mutex", NULL,
3086 MTX_DEF);
3087 #ifdef NETGRAPH_DEBUG
3088 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", NULL,
3089 MTX_DEF);
3090 mtx_init(&ngq_mtx, "netgraph item list mutex", NULL,
3091 MTX_DEF);
3092 #endif
3093 ng_qzone = uma_zcreate("NetGraph items", sizeof(struct ng_item),
3094 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0);
3095 uma_zone_set_max(ng_qzone, maxalloc);
3096 ng_qdzone = uma_zcreate("NetGraph data items", sizeof(struct ng_item),
3097 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0);
3098 uma_zone_set_max(ng_qdzone, maxdata);
3099 /* Autoconfigure number of threads. */
3100 if (numthreads <= 0)
3101 numthreads = mp_ncpus;
3102 /* Create threads. */
3103 for (i = 0; i < numthreads; i++) {
3104 if (kthread_create(ngthread, NULL, NULL,
3105 0, 0, "ng_queue%d", i)) {
3106 numthreads = i - 1;
3107 break;
3108 }
3109 }
3110 break;
3111 case MOD_UNLOAD:
3112 /* You can't unload it because an interface may be using it. */
3113 error = EBUSY;
3114 break;
3115 default:
3116 error = EOPNOTSUPP;
3117 break;
3118 }
3119 return (error);
3120 }
3121
3122 static moduledata_t netgraph_mod = {
3123 "netgraph",
3124 ngb_mod_event,
3125 (NULL)
3126 };
3127 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_NETGRAPH, SI_ORDER_MIDDLE);
3128 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family");
3129 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,"");
3130 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, "");
3131
3132 #ifdef NETGRAPH_DEBUG
3133 void
3134 dumphook (hook_p hook, char *file, int line)
3135 {
3136 printf("hook: name %s, %d refs, Last touched:\n",
3137 _NG_HOOK_NAME(hook), hook->hk_refs);
3138 printf(" Last active @ %s, line %d\n",
3139 hook->lastfile, hook->lastline);
3140 if (line) {
3141 printf(" problem discovered at file %s, line %d\n", file, line);
3142 }
3143 }
3144
3145 void
3146 dumpnode(node_p node, char *file, int line)
3147 {
3148 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n",
3149 _NG_NODE_ID(node), node->nd_type->name,
3150 node->nd_numhooks, node->nd_flags,
3151 node->nd_refs, node->nd_name);
3152 printf(" Last active @ %s, line %d\n",
3153 node->lastfile, node->lastline);
3154 if (line) {
3155 printf(" problem discovered at file %s, line %d\n", file, line);
3156 }
3157 }
3158
3159 void
3160 dumpitem(item_p item, char *file, int line)
3161 {
3162 printf(" ACTIVE item, last used at %s, line %d",
3163 item->lastfile, item->lastline);
3164 switch(item->el_flags & NGQF_TYPE) {
3165 case NGQF_DATA:
3166 printf(" - [data]\n");
3167 break;
3168 case NGQF_MESG:
3169 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item));
3170 break;
3171 case NGQF_FN:
3172 printf(" - fn@%p (%p, %p, %p, %d (%x))\n",
3173 _NGI_FN(item),
3174 _NGI_NODE(item),
3175 _NGI_HOOK(item),
3176 item->body.fn.fn_arg1,
3177 item->body.fn.fn_arg2,
3178 item->body.fn.fn_arg2);
3179 break;
3180 case NGQF_FN2:
3181 printf(" - fn2@%p (%p, %p, %p, %d (%x))\n",
3182 _NGI_FN2(item),
3183 _NGI_NODE(item),
3184 _NGI_HOOK(item),
3185 item->body.fn.fn_arg1,
3186 item->body.fn.fn_arg2,
3187 item->body.fn.fn_arg2);
3188 break;
3189 }
3190 if (line) {
3191 printf(" problem discovered at file %s, line %d\n", file, line);
3192 if (_NGI_NODE(item)) {
3193 printf("node %p ([%x])\n",
3194 _NGI_NODE(item), ng_node2ID(_NGI_NODE(item)));
3195 }
3196 }
3197 }
3198
3199 static void
3200 ng_dumpitems(void)
3201 {
3202 item_p item;
3203 int i = 1;
3204 TAILQ_FOREACH(item, &ng_itemlist, all) {
3205 printf("[%d] ", i++);
3206 dumpitem(item, NULL, 0);
3207 }
3208 }
3209
3210 static void
3211 ng_dumpnodes(void)
3212 {
3213 node_p node;
3214 int i = 1;
3215 mtx_lock(&ng_nodelist_mtx);
3216 SLIST_FOREACH(node, &ng_allnodes, nd_all) {
3217 printf("[%d] ", i++);
3218 dumpnode(node, NULL, 0);
3219 }
3220 mtx_unlock(&ng_nodelist_mtx);
3221 }
3222
3223 static void
3224 ng_dumphooks(void)
3225 {
3226 hook_p hook;
3227 int i = 1;
3228 mtx_lock(&ng_nodelist_mtx);
3229 SLIST_FOREACH(hook, &ng_allhooks, hk_all) {
3230 printf("[%d] ", i++);
3231 dumphook(hook, NULL, 0);
3232 }
3233 mtx_unlock(&ng_nodelist_mtx);
3234 }
3235
3236 static int
3237 sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS)
3238 {
3239 int error;
3240 int val;
3241 int i;
3242
3243 val = allocated;
3244 i = 1;
3245 error = sysctl_handle_int(oidp, &val, 0, req);
3246 if (error != 0 || req->newptr == NULL)
3247 return (error);
3248 if (val == 42) {
3249 ng_dumpitems();
3250 ng_dumpnodes();
3251 ng_dumphooks();
3252 }
3253 return (0);
3254 }
3255
3256 SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW,
3257 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items");
3258 #endif /* NETGRAPH_DEBUG */
3259
3260
3261 /***********************************************************************
3262 * Worklist routines
3263 **********************************************************************/
3264 /*
3265 * Pick a node off the list of nodes with work,
3266 * try get an item to process off it. Remove the node from the list.
3267 */
3268 static void
3269 ngthread(void *arg)
3270 {
3271 for (;;) {
3272 node_p node;
3273
3274 /* Get node from the worklist. */
3275 NG_WORKLIST_LOCK();
3276 while ((node = TAILQ_FIRST(&ng_worklist)) == NULL)
3277 NG_WORKLIST_SLEEP();
3278 TAILQ_REMOVE(&ng_worklist, node, nd_work);
3279 NG_WORKLIST_UNLOCK();
3280 CTR3(KTR_NET, "%20s: node [%x] (%p) taken off worklist",
3281 __func__, node->nd_ID, node);
3282 /*
3283 * We have the node. We also take over the reference
3284 * that the list had on it.
3285 * Now process as much as you can, until it won't
3286 * let you have another item off the queue.
3287 * All this time, keep the reference
3288 * that lets us be sure that the node still exists.
3289 * Let the reference go at the last minute.
3290 */
3291 for (;;) {
3292 item_p item;
3293 int rw;
3294
3295 NG_QUEUE_LOCK(&node->nd_input_queue);
3296 item = ng_dequeue(&node->nd_input_queue, &rw);
3297 if (item == NULL) {
3298 atomic_clear_int(&node->nd_flags, NGF_WORKQ);
3299 NG_QUEUE_UNLOCK(&node->nd_input_queue);
3300 break; /* go look for another node */
3301 } else {
3302 NG_QUEUE_UNLOCK(&node->nd_input_queue);
3303 NGI_GET_NODE(item, node); /* zaps stored node */
3304 ng_apply_item(node, item, rw);
3305 NG_NODE_UNREF(node);
3306 }
3307 }
3308 NG_NODE_UNREF(node);
3309 }
3310 }
3311
3312 /*
3313 * XXX
3314 * It's posible that a debugging NG_NODE_REF may need
3315 * to be outside the mutex zone
3316 */
3317 static void
3318 ng_worklist_add(node_p node)
3319 {
3320
3321 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED);
3322
3323 if ((node->nd_flags & NGF_WORKQ) == 0) {
3324 /*
3325 * If we are not already on the work queue,
3326 * then put us on.
3327 */
3328 atomic_set_int(&node->nd_flags, NGF_WORKQ);
3329 NG_NODE_REF(node); /* XXX fafe in mutex? */
3330 NG_WORKLIST_LOCK();
3331 TAILQ_INSERT_TAIL(&ng_worklist, node, nd_work);
3332 NG_WORKLIST_UNLOCK();
3333 CTR3(KTR_NET, "%20s: node [%x] (%p) put on worklist", __func__,
3334 node->nd_ID, node);
3335 NG_WORKLIST_WAKEUP();
3336 } else {
3337 CTR3(KTR_NET, "%20s: node [%x] (%p) already on worklist",
3338 __func__, node->nd_ID, node);
3339 }
3340 }
3341
3342
3343 /***********************************************************************
3344 * Externally useable functions to set up a queue item ready for sending
3345 ***********************************************************************/
3346
3347 #ifdef NETGRAPH_DEBUG
3348 #define ITEM_DEBUG_CHECKS \
3349 do { \
3350 if (NGI_NODE(item) ) { \
3351 printf("item already has node"); \
3352 kdb_enter_why(KDB_WHY_NETGRAPH, "has node"); \
3353 NGI_CLR_NODE(item); \
3354 } \
3355 if (NGI_HOOK(item) ) { \
3356 printf("item already has hook"); \
3357 kdb_enter_why(KDB_WHY_NETGRAPH, "has hook"); \
3358 NGI_CLR_HOOK(item); \
3359 } \
3360 } while (0)
3361 #else
3362 #define ITEM_DEBUG_CHECKS
3363 #endif
3364
3365 /*
3366 * Put mbuf into the item.
3367 * Hook and node references will be removed when the item is dequeued.
3368 * (or equivalent)
3369 * (XXX) Unsafe because no reference held by peer on remote node.
3370 * remote node might go away in this timescale.
3371 * We know the hooks can't go away because that would require getting
3372 * a writer item on both nodes and we must have at least a reader
3373 * here to be able to do this.
3374 * Note that the hook loaded is the REMOTE hook.
3375 *
3376 * This is possibly in the critical path for new data.
3377 */
3378 item_p
3379 ng_package_data(struct mbuf *m, int flags)
3380 {
3381 item_p item;
3382
3383 if ((item = ng_alloc_item(NGQF_DATA, flags)) == NULL) {
3384 NG_FREE_M(m);
3385 return (NULL);
3386 }
3387 ITEM_DEBUG_CHECKS;
3388 item->el_flags |= NGQF_READER;
3389 NGI_M(item) = m;
3390 return (item);
3391 }
3392
3393 /*
3394 * Allocate a queue item and put items into it..
3395 * Evaluate the address as this will be needed to queue it and
3396 * to work out what some of the fields should be.
3397 * Hook and node references will be removed when the item is dequeued.
3398 * (or equivalent)
3399 */
3400 item_p
3401 ng_package_msg(struct ng_mesg *msg, int flags)
3402 {
3403 item_p item;
3404
3405 if ((item = ng_alloc_item(NGQF_MESG, flags)) == NULL) {
3406 NG_FREE_MSG(msg);
3407 return (NULL);
3408 }
3409 ITEM_DEBUG_CHECKS;
3410 /* Messages items count as writers unless explicitly exempted. */
3411 if (msg->header.cmd & NGM_READONLY)
3412 item->el_flags |= NGQF_READER;
3413 else
3414 item->el_flags |= NGQF_WRITER;
3415 /*
3416 * Set the current lasthook into the queue item
3417 */
3418 NGI_MSG(item) = msg;
3419 NGI_RETADDR(item) = 0;
3420 return (item);
3421 }
3422
3423
3424
3425 #define SET_RETADDR(item, here, retaddr) \
3426 do { /* Data or fn items don't have retaddrs */ \
3427 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \
3428 if (retaddr) { \
3429 NGI_RETADDR(item) = retaddr; \
3430 } else { \
3431 /* \
3432 * The old return address should be ok. \
3433 * If there isn't one, use the address \
3434 * here. \
3435 */ \
3436 if (NGI_RETADDR(item) == 0) { \
3437 NGI_RETADDR(item) \
3438 = ng_node2ID(here); \
3439 } \
3440 } \
3441 } \
3442 } while (0)
3443
3444 int
3445 ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr)
3446 {
3447 hook_p peer;
3448 node_p peernode;
3449 ITEM_DEBUG_CHECKS;
3450 /*
3451 * Quick sanity check..
3452 * Since a hook holds a reference on it's node, once we know
3453 * that the peer is still connected (even if invalid,) we know
3454 * that the peer node is present, though maybe invalid.
3455 */
3456 if ((hook == NULL) ||
3457 NG_HOOK_NOT_VALID(hook) ||
3458 NG_HOOK_NOT_VALID(peer = NG_HOOK_PEER(hook)) ||
3459 NG_NODE_NOT_VALID(peernode = NG_PEER_NODE(hook))) {
3460 NG_FREE_ITEM(item);
3461 TRAP_ERROR();
3462 return (ENETDOWN);
3463 }
3464
3465 /*
3466 * Transfer our interest to the other (peer) end.
3467 */
3468 NG_HOOK_REF(peer);
3469 NG_NODE_REF(peernode);
3470 NGI_SET_HOOK(item, peer);
3471 NGI_SET_NODE(item, peernode);
3472 SET_RETADDR(item, here, retaddr);
3473 return (0);
3474 }
3475
3476 int
3477 ng_address_path(node_p here, item_p item, char *address, ng_ID_t retaddr)
3478 {
3479 node_p dest = NULL;
3480 hook_p hook = NULL;
3481 int error;
3482
3483 ITEM_DEBUG_CHECKS;
3484 /*
3485 * Note that ng_path2noderef increments the reference count
3486 * on the node for us if it finds one. So we don't have to.
3487 */
3488 error = ng_path2noderef(here, address, &dest, &hook);
3489 if (error) {
3490 NG_FREE_ITEM(item);
3491 return (error);
3492 }
3493 NGI_SET_NODE(item, dest);
3494 if ( hook) {
3495 NG_HOOK_REF(hook); /* don't let it go while on the queue */
3496 NGI_SET_HOOK(item, hook);
3497 }
3498 SET_RETADDR(item, here, retaddr);
3499 return (0);
3500 }
3501
3502 int
3503 ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr)
3504 {
3505 node_p dest;
3506
3507 ITEM_DEBUG_CHECKS;
3508 /*
3509 * Find the target node.
3510 */
3511 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */
3512 if (dest == NULL) {
3513 NG_FREE_ITEM(item);
3514 TRAP_ERROR();
3515 return(EINVAL);
3516 }
3517 /* Fill out the contents */
3518 NGI_SET_NODE(item, dest);
3519 NGI_CLR_HOOK(item);
3520 SET_RETADDR(item, here, retaddr);
3521 return (0);
3522 }
3523
3524 /*
3525 * special case to send a message to self (e.g. destroy node)
3526 * Possibly indicate an arrival hook too.
3527 * Useful for removing that hook :-)
3528 */
3529 item_p
3530 ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg)
3531 {
3532 item_p item;
3533
3534 /*
3535 * Find the target node.
3536 * If there is a HOOK argument, then use that in preference
3537 * to the address.
3538 */
3539 if ((item = ng_alloc_item(NGQF_MESG, NG_NOFLAGS)) == NULL) {
3540 NG_FREE_MSG(msg);
3541 return (NULL);
3542 }
3543
3544 /* Fill out the contents */
3545 item->el_flags |= NGQF_WRITER;
3546 NG_NODE_REF(here);
3547 NGI_SET_NODE(item, here);
3548 if (hook) {
3549 NG_HOOK_REF(hook);
3550 NGI_SET_HOOK(item, hook);
3551 }
3552 NGI_MSG(item) = msg;
3553 NGI_RETADDR(item) = ng_node2ID(here);
3554 return (item);
3555 }
3556
3557 /*
3558 * Send ng_item_fn function call to the specified node.
3559 */
3560
3561 int
3562 ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2)
3563 {
3564
3565 return ng_send_fn1(node, hook, fn, arg1, arg2, NG_NOFLAGS);
3566 }
3567
3568 int
3569 ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2,
3570 int flags)
3571 {
3572 item_p item;
3573
3574 if ((item = ng_alloc_item(NGQF_FN, flags)) == NULL) {
3575 return (ENOMEM);
3576 }
3577 item->el_flags |= NGQF_WRITER;
3578 NG_NODE_REF(node); /* and one for the item */
3579 NGI_SET_NODE(item, node);
3580 if (hook) {
3581 NG_HOOK_REF(hook);
3582 NGI_SET_HOOK(item, hook);
3583 }
3584 NGI_FN(item) = fn;
3585 NGI_ARG1(item) = arg1;
3586 NGI_ARG2(item) = arg2;
3587 return(ng_snd_item(item, flags));
3588 }
3589
3590 /*
3591 * Send ng_item_fn2 function call to the specified node.
3592 *
3593 * If an optional pitem parameter is supplied, its apply
3594 * callback will be copied to the new item. If also NG_REUSE_ITEM
3595 * flag is set, no new item will be allocated, but pitem will
3596 * be used.
3597 */
3598 int
3599 ng_send_fn2(node_p node, hook_p hook, item_p pitem, ng_item_fn2 *fn, void *arg1,
3600 int arg2, int flags)
3601 {
3602 item_p item;
3603
3604 KASSERT((pitem != NULL || (flags & NG_REUSE_ITEM) == 0),
3605 ("%s: NG_REUSE_ITEM but no pitem", __func__));
3606
3607 /*
3608 * Allocate a new item if no supplied or
3609 * if we can't use supplied one.
3610 */
3611 if (pitem == NULL || (flags & NG_REUSE_ITEM) == 0) {
3612 if ((item = ng_alloc_item(NGQF_FN2, flags)) == NULL)
3613 return (ENOMEM);
3614 if (pitem != NULL)
3615 item->apply = pitem->apply;
3616 } else {
3617 if ((item = ng_realloc_item(pitem, NGQF_FN2, flags)) == NULL)
3618 return (ENOMEM);
3619 }
3620
3621 item->el_flags = (item->el_flags & ~NGQF_RW) | NGQF_WRITER;
3622 NG_NODE_REF(node); /* and one for the item */
3623 NGI_SET_NODE(item, node);
3624 if (hook) {
3625 NG_HOOK_REF(hook);
3626 NGI_SET_HOOK(item, hook);
3627 }
3628 NGI_FN2(item) = fn;
3629 NGI_ARG1(item) = arg1;
3630 NGI_ARG2(item) = arg2;
3631 return(ng_snd_item(item, flags));
3632 }
3633
3634 /*
3635 * Official timeout routines for Netgraph nodes.
3636 */
3637 static void
3638 ng_callout_trampoline(void *arg)
3639 {
3640 item_p item = arg;
3641
3642 ng_snd_item(item, 0);
3643 }
3644
3645
3646 int
3647 ng_callout(struct callout *c, node_p node, hook_p hook, int ticks,
3648 ng_item_fn *fn, void * arg1, int arg2)
3649 {
3650 item_p item, oitem;
3651
3652 if ((item = ng_alloc_item(NGQF_FN, NG_NOFLAGS)) == NULL)
3653 return (ENOMEM);
3654
3655 item->el_flags |= NGQF_WRITER;
3656 NG_NODE_REF(node); /* and one for the item */
3657 NGI_SET_NODE(item, node);
3658 if (hook) {
3659 NG_HOOK_REF(hook);
3660 NGI_SET_HOOK(item, hook);
3661 }
3662 NGI_FN(item) = fn;
3663 NGI_ARG1(item) = arg1;
3664 NGI_ARG2(item) = arg2;
3665 oitem = c->c_arg;
3666 if (callout_reset(c, ticks, &ng_callout_trampoline, item) == 1 &&
3667 oitem != NULL)
3668 NG_FREE_ITEM(oitem);
3669 return (0);
3670 }
3671
3672 /* A special modified version of untimeout() */
3673 int
3674 ng_uncallout(struct callout *c, node_p node)
3675 {
3676 item_p item;
3677 int rval;
3678
3679 KASSERT(c != NULL, ("ng_uncallout: NULL callout"));
3680 KASSERT(node != NULL, ("ng_uncallout: NULL node"));
3681
3682 rval = callout_stop(c);
3683 item = c->c_arg;
3684 /* Do an extra check */
3685 if ((rval > 0) && (c->c_func == &ng_callout_trampoline) &&
3686 (NGI_NODE(item) == node)) {
3687 /*
3688 * We successfully removed it from the queue before it ran
3689 * So now we need to unreference everything that was
3690 * given extra references. (NG_FREE_ITEM does this).
3691 */
3692 NG_FREE_ITEM(item);
3693 }
3694 c->c_arg = NULL;
3695
3696 return (rval);
3697 }
3698
3699 /*
3700 * Set the address, if none given, give the node here.
3701 */
3702 void
3703 ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr)
3704 {
3705 if (retaddr) {
3706 NGI_RETADDR(item) = retaddr;
3707 } else {
3708 /*
3709 * The old return address should be ok.
3710 * If there isn't one, use the address here.
3711 */
3712 NGI_RETADDR(item) = ng_node2ID(here);
3713 }
3714 }
3715
3716 #define TESTING
3717 #ifdef TESTING
3718 /* just test all the macros */
3719 void
3720 ng_macro_test(item_p item);
3721 void
3722 ng_macro_test(item_p item)
3723 {
3724 node_p node = NULL;
3725 hook_p hook = NULL;
3726 struct mbuf *m;
3727 struct ng_mesg *msg;
3728 ng_ID_t retaddr;
3729 int error;
3730
3731 NGI_GET_M(item, m);
3732 NGI_GET_MSG(item, msg);
3733 retaddr = NGI_RETADDR(item);
3734 NG_SEND_DATA(error, hook, m, NULL);
3735 NG_SEND_DATA_ONLY(error, hook, m);
3736 NG_FWD_NEW_DATA(error, item, hook, m);
3737 NG_FWD_ITEM_HOOK(error, item, hook);
3738 NG_SEND_MSG_HOOK(error, node, msg, hook, retaddr);
3739 NG_SEND_MSG_ID(error, node, msg, retaddr, retaddr);
3740 NG_SEND_MSG_PATH(error, node, msg, ".:", retaddr);
3741 NG_FWD_MSG_HOOK(error, node, item, hook, retaddr);
3742 }
3743 #endif /* TESTING */
3744
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